Deep neural network-based phase calibration in integrated optical phased arrays

Calibrating the phase in integrated optical phased arrays (OPAs) is a crucial procedure for addressing phase errors and achieving the desired beamforming results. In this paper, we introduce a novel phase calibration methodology based on a deep neural network (DNN) architecture to enhance beamforming in integrated OPAs. Our methodology focuses on precise phase control, individually tailored to each of the 64 OPA channels, incorporating electro-optic phase shifters. To effectively handle the inherent complexity arising from the numerous voltage set combinations required for phase control across the 64 channels, we employ a tandem network architecture, further optimizing it through selective data sorting and hyperparameter tuning. To validate the effectiveness of the trained DNN model, we compared its performance with 20 reference beams obtained through the hill climbing algorithm. Despite an average intensity reduction of 0.84 dB in the peak values of the beams compared to the reference beams, our experimental results demonstrate substantial agreements between the DNN-predicted beams and the reference beams, accompanied by a slight decrease of 0.06 dB in the side-mode-suppression-ratio. These results underscore the practical effectiveness of the DNN model in OPA beamforming, highlighting its potential in scenarios that necessitate the intelligent and time-efficient calibration of multiple beams.

POS0836 EFFICACY OF MEPOLIZUMAB IN PATIENTS WITH EOSINOPHILIC GRANULOMATOSIS WITH POLYANGIITIS AND A VASCULITIC PHENOTYPE

Background

Patients with eosinophilic granulomatosis with polyangiitis (EGPA) can present with vasculitic or eosinophilic phenotypes.1 The Phase III MIRRA study demonstrated that patients with EGPA spent more time in remission and had reduced oral corticosteroid (OCS) use with mepolizumab versus placebo.2

Objectives

To evaluate the efficacy of mepolizumab in patients with a vasculitic EGPA phenotype enrolled in the MIRRA study.

Methods

MIRRA was a Phase III, multicentre, double-blind, parallel-group trial in adult patients with relapsing/refractory EGPA and ≥4 weeks stable OCS treatment. Patients were randomised to receive standard of care plus mepolizumab (300 mg subcutaneously every 4 weeks) or placebo for 52 weeks. Primary endpoints were: accrued weeks of remission (defined as Birmingham Vasculitis Activity Score [BVAS] of 0 and OCS dose ≤4 mg/day prednisolone or equivalent) over the 52-week study period categorised in weeks (0, >0 to <12, 12 to <24, 24 to <36 and ≥36 weeks), and the proportion of patients in remission at both Weeks 36 and 48. This post hoc analysis used data from the MIRRA study to evaluate these endpoints according to patients’ antineutrophil cytoplasmic antibody (ANCA) history (current or previous positive test for myeloperoxidase[MPO]/proteinase 3[PR3]-ANCA at study baseline versus no history of a positive MPO/PR3-ANCA test at baseline), baseline BVAS (=0 vs >0) and Vasculitis Damage Index (VDI) score (<5 vs ≥5). Types of disease relapse (vasculitis [BVAS >0], asthma [active asthma symptoms and/or signs with a worsening in Asthma Control Questionnaire-6 score] and sinonasal [active nasal and/or sinus disease with a worsening in ≥1 sinonasal symptom questions]) reported during the treatment period were also described. EGPA disease characteristics focusing on vasculitic components were assessed in patients who did and did not achieve remission at any point during the study.

Results

Of the 136 patients in the study, 26 (19%) had a history of a positive ANCA test at study baseline and 110 (81%) did not. In addition, 51 (38%) had a BVAS =0 at baseline while 85 (63%) had a BVAS >0; 74 (54%) had a VDI <5 at baseline and 62 (46%) had a VDI ≥5. Accrued remission duration was greater with mepolizumab versus placebo, irrespective of ANCA positive status, baseline BVAS or baseline VDI score (Figure 1). Across all the subgroups, a larger proportion of patients achieved remission at both Weeks 36 and 48 with mepolizumab versus placebo (Figure 1). Among patients receiving mepolizumab, the numbers (proportion) of patients achieving remission at both Weeks 36 and 48 were: 7 (54%) for patients with a history of an ANCA-positive test and 15 (27%) for patients without a history of an ANCA-positive test; 14 (45%) in the BVAS =0 and 8 (22%) in the BVAS >0 groups; 11 (29%) in the VDI score <5 and 11 (37%) in the VDI score ≥5 groups. Mepolizumab reduced all types of disease relapse assessed during the treatment period, including vasculitis, asthma and sinonasal relapses, compared with placebo. Vasculitic characteristics including neuropathy, glomerulonephritis, alveolar haemorrhage, palpable purpura and ANCA positivity were generally similar among patients who did and did not achieve remission during the study.

Figure 1.

Mepolizumab efficacy by patient baseline characteristics

ANCA, antineutrophil cytoplasmic antibody; BVAS, Birmingham Vasculitis Activity Score; CI, confidence interval; NA, data not available – estimate could not be calculated owing to a lack of patients in the placebo group achieving remission at Weeks 36 and 48; VDI, Vasculitis Damage Index.

Conclusion

Mepolizumab is associated with clinical benefits in patients with EGPA, including those with and without a vasculitic phenotype.

References

[1]Latorre M et al. Eur Respir J. 2013;42(Suppl 57):1797.

[2]Wechsler ME et al. N Engl J Med. 2017;376(20):1921–32.

Acknowledgements

Funding: GSK (MEA115921; NCT02020889); the Division of Intramural Research, NIAID, NIH funded in part time spent on this abstract by one of the authors (PK).

Disclosure of Interests

Benjamin Terrier Consultant of: Roche, Chugai, GSK, AstraZeneca, Bristol Myers Squibb, Terumo BCT, Sanofi, LFB and Grifols, David Jayne Speakers bureau: Amgen Vifor, Consultant of: AstraZeneca, Aurinia, BMS, Boehringer Ingelheim, ChemoCentryx, GSK, Janssen, Novartis, Roche/Genentech, Takeda and Vifor, Grant/research support from: AstraZeneca, Aurinia, BMS, Boehringer Ingelheim, ChemoCentryx, GSK, Janssen, Novartis, Roche/Genentech, Takeda and Vifor, Bernhard Hellmich Speakers bureau: AbbVie, BMS, Boehringer Ingelheim, Chugai, GSK, InflaRx, Novartis, Pfizer, Roche and Vifor Pharma, Consultant of: AbbVie, BMS, Boehringer Ingelheim, Chugai, GSK, InflaRx, Novartis, Pfizer, Roche and Vifor Pharma, Grant/research support from: Ab2Bio, AbbVie, AstraZeneca, Bristol Myers Squibb, ChemoCentryx, GSK, InflaRx, Kiniksa, Nippon Kayaku, Novartis, Roche, and Sanofi (my institution received payments for participation in multicentre clinical trials and the institution or myself did not receive money for any other kind of research projects), Jane H. Bentley Shareholder of: GSK, Employee of: GSK, Jonathan Steinfeld Shareholder of: GSK, Employee of: GSK, Steven W Yancey Shareholder of: GSK, Employee of: GSK, Namhee Kwon Shareholder of: GSK, Employee of: GSK, Praveen Akuthota Paid instructor for: AstraZeneca, Consultant of: AstraZeneca, GSK, Sanofi, Grant/research support from: GSK, AstraZeneca and Regeneron, Paneez Khoury: None declared, Lee Baylis Shareholder of: GSK, Employee of: GSK, Michael Wechsler Consultant of: GSK, Genentech, Sanofi, Regeneron, AstraZeneca, Teva, Novartis, Boehringer Ingelheim, Sentien, and Equillium, Grant/research support from: National Institute of Allergy and Infectious Diseases and the National Heart, Lung, and Blood Institute

Recombinant BRICHOS chaperone domains delivered to mouse brain parenchyma by focused ultrasound and microbubbles are internalized by hippocampal and cortical neurons

The BRICHOS domain is found in human precursor proteins associated with cancer, dementia (Bri2) and amyloid lung disease (proSP-C). Recombinant human (rh) proSP-C and Bri2 BRICHOS domains delay amyloid-β peptide (Aβ) fibril formation and reduce associated toxicity in vitro and their overexpression reduces Aβ neurotoxicity in animal models of Alzheimer's disease. After intravenous administration in wild-type mice, rh Bri2, but not proSP-C, BRICHOS was detected in the brain parenchyma, suggesting that Bri2 BRICHOS selectively bypasses the blood-brain barrier (BBB). Here, our objective was to increase the brain delivery of rh proSP-C (trimer of 18 kDa subunits) and Bri2 BRICHOS (monomer to oligomer of 15 kDa subunits) using focused ultrasound combined with intravenous microbubbles (FUS + MB), which enables targeted and transient opening of the BBB. FUS + MB was targeted to one hemisphere of wild type mice and BBB opening in the hippocampal region was confirmed by magnetic resonance imaging. Two hours after FUS + MB brain histology showed no signs of tissue damage and immunohistochemistry showed abundant delivery to the brain parenchyma in 13 out of 16 cases given 10 mg/kg of proSP-C or Bri2 BRICHOS domains. The Bri2, but not proSP-C BRICHOS domain was detected also in the non-targeted hemisphere. ProSP-C and Bri2 BRICHOS domains were taken up by a subset of neurons in the hippocampus and cortex, and were detected to a minor extent in early endosomes. These results indicate that rh Bri2, but not proSP-C, BRICHOS, can be efficiently delivered into the mouse brain parenchyma and that both BRICHOS domains can be internalized by cell-specific mechanisms.

Patients' beliefs and behaviors related to treatment adherence in patients with asthma requiring maintenance treatment in Asia

Objectives

To identify patients’ beliefs or behaviors related to treatment adherence and to assess association between asthma control and adherence in Asian patients with asthma.

Methods

We conducted a cross-sectional observational study of adult patients with asthma from specialist clinics in six Asian countries. Patients who were deemed by their treating physicians to require a maintenance treatment with an inhaler for at least 1 year were recruited. Patients completed a 12-item questionnaire related to health beliefs and behaviors, the 8-item Morisky Medication Adherence Scale (MMAS-8), the Asthma Control Test (ACT™), and the Standardized Asthma Quality of Life Questionnaire (AQLQ-S).

Results

Of the 1054 patients recruited, 99% were current users of inhaled corticosteroids. The mean ACT score was 20.0 ± 4.5 and 64% had well-controlled asthma. The mean MMAS-8 score was 5.5 ± 2.0 and 53% were adherent. Adherence was significantly associated with patients’ understanding of the disease and inhaler techniques, and with patients’ acceptance of inhaler medicines in terms of benefits, safety, convenience, and cost (p < 0.01 for all). In multivariate analysis, three questions related to patients’ acceptance of inhaler medicines remained significantly associated with poor adherence, after adjusting for potential confounders: “I am not sure inhaler type medicines work well” (p = 0.001), “Taking medicines more than once a day is inconvenient” (p = 0.002), and “Sometimes I skip my inhaler to use it over a longer period” (p < 0.001).

Conclusions

Our study showed that patients’ acceptance of the benefits, convenience and cost of inhaler medications have a significant impact on treatment adherence in the participating Asian countries.

Effect of age on atherogenicity of LDL and inflammatory markers in healthy women

BACKGROUND AND AIM

Since using LDL level alone is insufficient as a method to identify individuals with incident coronary artery disease (CAD), other factors may be implicated in the pathogenesis of CAD. Additionally, controversy still remains regarding whether there is an age-related increase in circulating cytokines in healthy individuals. We investigated the influence of age on atherogenicity of LDL and inflammatory markers in healthy women.

METHODS AND RESULTS

Two thousand nine hundred forty four healthy women form 30-79 years old (23.3 ± 0.05 kg/m²) were categorized into 5 age groups: 30-39, 40-49, 50-59, 60-69 and 70-79 years. BMI, smoking, drinking, and metabolic syndrome prevalence adjusted mean values of total-cholesterol progressively increased from the group age 30-39 years to the group age 40-49 and 50-59 years and thereafter decreased in the group age 60-69 and 70-79 years. Serum concentrations of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were higher in women aged 60-79 years than women aged 30-59 years. Plasma ox-LDL levels increased in the group age 50-59 years compared with the group age 30-39 and 40-49 years and further increased in the group age 60-69 and 70-79 years. Mean values of LDL particle size were smaller in women aged 60-79 years than those in women aged 30-59 years. After adjustment for BMI, smoking, drinking, and metabolic syndrome status, age was positively correlated with LDL-cholesterol (r = 0.095, P < 0.001), oxidized LDL (r = 0.305, P < 0.001), hs-CRP (r = 0.150, P < 0.001), TNF-α (r = 0.171, P < 0.001) and IL-6 (r = 0.294, P < 0.001) and negatively with LDL particle size (r = -0.239, P < 0.001).

CONCLUSION

Our results indicate that LDL atherogenicity and inflammatory mediators can be better markers of CAD risk than known risk factors such as elevated concentrations of total- and LDL-cholesterol, decreased HDL-cholesterol levels and smoking in old healthy women.

Pediatric asthma control in Asia: phase 2 of the Asthma Insights and Reality in Asia-Pacific (AIRIAP 2) survey

BACKGROUND

We conducted Phase 2 of the Asthma Insights and Reality in the Asia-Pacific (AIRIAP 2) survey in 2006 to determine the level of asthma control in this region and the validity of the Asthma Control Test (ACT) and childhood ACT (C-ACT) in relation to asthma control.

METHODS

Pediatric participants (0 to <16 years; N = 988) with diagnosed asthma and current asthma symptoms or taking anti-asthma medications were recruited from 12 geographic areas in Asia. The survey consisted of the AIRIAP 2 questionnaire (asthma symptoms, use of urgent healthcare services and anti-asthma medication) and the ACT or C-ACT (English or Chinese translations only), both administered in the participant's preferred language. A symptom control index based on the Global Initiative for Asthma criteria (except lung function) was used to classify asthma control status.

RESULTS

Most participants had inadequately controlled asthma ('uncontrolled' = 53.4%, 528/988; 'partly controlled' = 44.0%, 435/988). Only 2.5% (25/988) had 'controlled' asthma. Demand for urgent healthcare services (51.7%, 511/988) and use of short-acting beta-agonists (55.2%, 545/988) was high. The optimal ACT and C-ACT cutoff score for detecting uncontrolled asthma (compared with controlled or partly controlled asthma) was determined to be ≤19 (receiver operating characteristic analysis) with good agreement between the ACT and C-ACT and the symptom control index.

CONCLUSIONS

Findings from this survey show that asthma control is suboptimal in many children in the Asia-Pacific region. Practical tools, such as the ACT or C-ACT, may help clinicians assess asthma control and facilitate adjustment of asthma medication.

Fast microtomography using bright monochromatic x-rays

A fast microtomography system for high-resolution high-speed imaging has been developed using bright monochromatic x-rays at the BL29XU beamline of SPring-8. The shortest scan time for microtomography we attained was 0.25 s in 1.25 μm effective pixel size by combining the bright monochromatic x-rays, a fast rotating sample stage, and a high performance x-ray imaging detector. The feasibility of the tomography system was successfully demonstrated by visualization of rising bubbles in a viscous liquid, an interesting issue in multiphase flow physics. This system also provides a high spatial (a measurable feature size of 300 nm) or a very high temporal (9.8 μs) resolution in radiographs.