Tailored Synthesis of Heterogenous 2D TMDs and Their Spectroscopic Characterization

Two-dimensional (2D) vertical van der Waals heterostructures (vdWHs) show great potential across various applications. However, synthesizing large-scale structures poses challenges owing to the intricate growth parameters, forming unexpected hybrid film structures. Thus, precision in synthesis and thorough structural analysis are essential aspects. In this study, we successfully synthesized large-scale structured 2D transition metal dichalcogenides (TMDs) via chemical vapor deposition using metal oxide (WO3 and MoO3) thin films and a diluted H2S precursor, individual MoS2, WS2 films and various MoS2/WS2 hybrid films (Type I: MoxW1-xS2 alloy; Type II: MoS2/WS2 vdWH; Type III: MoS2 dots/WS2). Structural analyses, including optical microscopy, Raman spectroscopy, transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy, and cross-sectional imaging revealed that the A1g and E2g modes of WS2 and MoS2 were sensitive to structural variations, enabling hybrid structure differentiation. Type II showed minimal changes in the MoS2's A1g mode, while Types I and III exhibited a ~2.8 cm-1 blue shift. Furthermore, the A1g mode of WS2 in Type I displayed a 1.4 cm-1 red shift. These variations agreed with the TEM-observed microstructural features, demonstrating strain effects on the MoS2-WS2 interfaces. Our study provides insights into the structural features of diverse hybrid TMD materials, facilitating their differentiation through Raman spectroscopy.

POS0527 ANTI-CCP POSITIVE INDIVIDUALS AT RISK OF PROGRESSION TO INFLAMMATORY ARTHRITIS: WHAT HAPPENS TO BIOMARKERS PRIOR TO PROGRESSION?

Background

Although many predictors of progression to inflammatory arthritis (IA) have been identified at first visit in individuals at risk of developing IA, their fluctuation during follow-up is largely unknown.

Objectives

To describe the changes in relevant biomarkers, which precede arthritis development in anti-CCP positive at risk individuals.

Methods

In a single centre prospective observational cohort of anti-CCP positive individuals with new musculoskeletal symptoms but without clinical arthritis, 394 individuals with at least 3 available longitudinal datapoints including first, second and last records (progression excluded), were selected. Data on anti-CCP2 antibodies (CCP2), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), early morning stiffness duration (EMS), tender joint count on examination (TJC28), health assessment questionnaire (HAQ), absence from work in the last 3 months (sick days), and ultrasound power Doppler signal (PD) grade ≥ 1 in small joints, were assessed. Mixed model analysis on repeated measures (MANOVA) were performed, missing data were not imputed.

Results

Of the 394 selected individuals, 82 (21%) progressed to IA. In those who progressed, last visit was at a mean (SD) of 6.1 (8) months prior to progression, and total follow-up duration was 33.7 months (26.7) versus 46.5 months (30.2) for those who did not.

Within group analysis:in the progressor group there was a significant increase in the value of biomarkers at the visit prior progression for CCP2 +, RF +, EMS, HAQ, and the number of joints with a PD grade ≥ 1 (Figure 1, Table 1). For sick days from work prior last visit, the increase was non-significant.

Table 1.

Mixed model ANOVA on repeated measures: pairwise comparison

BiomarkerMean (SD)at last visitAnalysis between groupsAnalysis within groupsP-value between groups at last visitP-value between second and last visit within the progressor groupP-value between second and last visit within non- progressor groupWithin subject effectCCP2NP: 71 (108)p<0.001P=0.008P=1.000F(2/257)=3P: 169 (131)Pŋ2= 0.017P=0.077RFNP: 37 (73)P<0.001P=0.012P=0.973F(2/304)=15P: 185 (180)Pŋ2= 0.084P<0.001ESRNP: 11 (9)p<0.001P=1.000P=0.614F(2/580)=0.1P: 22 (21)Pŋ2< 0.001P=0.877EMSNP: 26 (68)P=0.010P=0.006P=1.000F(2/710)=4Pŋ2= 0.018P:58 (120)P=0.011TJC28NP: 0.5 (1.5)P<0.001P=1.000P<0.001F(2/784)=10P: 3 (5.5)Pŋ2< 0.025P<0.001Number of joints PD ≥1NP: 0.7 (2)P=0.020P=0.001P=0.055F(2/318)=4P: 1 (2)Pŋ2= 0.025P=0.014HAQNP: 0.5 (0.6)P=0.105P=0.016P=1.000F(2/494)=2.5P: 0.7 (0.8)Pŋ2= 0.0.009P=0.086Number of sick daysNP: 2 (6)P=0.204P=0.457P=0.492F(2/360)=4(Between visit 1 and 3: p=0.042)Pŋ2= 0.021 P=0.021P: 4 (13)

NP: Non progressors, P: progressors, Pŋ2: Partial ŋ2

+ for these results the assumption of homogeneity of variance was violated, as assessed by Levene’s test for equality of variances.

In the non-progressor group, only TJC28 and sick days showed significant decrease between first and last visit.

Between groups analysis showed significant differences at last visit for the following biomarkers -CCP2 +, RF +, ESR, EMS, TJC28, and number of joints PD grade ≥ 1. The difference in HAQ and sick days was non-significant (Figure 1, Table 1). A significant difference was also shown in all visits for CCP2 + and RF +, and at the second visit for TJC28.

For PD grade ≥ 1, differences at last visit within progressor group and between groups were only significant after selection of last visits < 3 months before progression.

Conclusion

These results show for the first time significant changes in relevant biomarkers prior to progression to IA with individual biomarkers having different trajectories. Clinical markers (EMS, TJC28, and HAQ) and ultrasound changed late, whilst immunological (CCP2 and RF values) and inflammation biomarkers (ESR) were different from baseline. These data provide valuable information for longitudinal monitoring of biomarkers, further analysis will show if these changes have predictive value for imminent progression to IA.

Disclosure of Interests

Laurence Duquenne: None declared, Kate Harnden: None declared, Leticia Garcia-Montoya: None declared, Navkiran Sidhu: None declared, Jacqueline Nam: None declared, Kulveer Mankia Speakers bureau: AbbVie, Lilly, UCB, Grant/research support from: Gilead, Lilly, Paul Emery Speakers bureau: AbbVie, Gilead, Lilly, Novartis, Consultant of: BMS, AbbVie, MSD, Pfizer, Novartis, Roche, Grant/research support from: Abbvie, BMS, Lilly, Samsung.

Direct Pattern Growth of Carbon Nanomaterials by Laser Scribing on Spin-Coated Cu-PI Composite Films and Their Gas Sensor Application

The excellent physical and chemical properties of carbon nanomaterials render them suitable for application in gas sensors. However, the synthesis of carbon nanomaterials using high-temperature furnaces is time consuming and expensive. In this study, we synthesize a carbon nanomaterial using local laser-scribing on a substrate coated with a Cu-embedded polyimide (PI) thin film to reduce the processing time and cost. Spin coating using a Cu-embedded PI solution is performed to deposit a Cu-embedded PI thin film (Cu@PI) on a quartz substrate, followed by the application of a pulsed laser for carbonization. In contrast to a pristine PI solution-based PI thin film, the laser absorption of the Cu-embedded PI thin film based on Cu@PI improved. The laser-scribed carbon nanomaterial synthesized using Cu@PI exhibits a three-dimensional structure that facilitates gas molecule absorption, and when it is exposed to NO₂ and NH₃, its electrical resistance changes by −0.79% and +0.33%, respectively.

POS0464 IS IT POSSIBLE TO IDENTIFY INDIVIDUALS AT IMMINENT-RISK OF SUB-CLINICAL JOINT INVOLVEMENT?

Background:

In anti-CCP antibody (Ab) positive at-risk individuals with MSK symptoms but without clinical synovitis, the detection of ultrasound (US) subclinical inflammation is associated with an increased risk of progression to inflammatory arthritis (IA) 1. Studies suggest that in these at-risk individuals, MSK symptoms develop before subclinical joint inflammation occurs on US. As such, anti-CCP Ab positive individuals with MSK symptoms in the absence of clinical or sub-clinical inflammation may be at the critical time-point for preventive treatments, before joint inflammation occurs and eventually becomes established (i.e., before the ‘second-hit’ in RA pathogenesis); however, identifying these individuals is challenging.

Objectives:

To identify, in second generation anti-CCP Ab (CCP2+) at-risk individuals with MSK symptoms, but without clinical or sub-clinical synovitis, predictors of US sub-clinical synovitis.

Methods:

In 186 CCP2+ at-risk individuals with normal baseline US scan (i.e., no synovitis or bone erosions), and a complete dataset, US data were analyzed at 6, 12 months, then annually until occurrence of IA. US synovitis was identified according to the EULAR/OMERACT definitions2. Relevant demographic (age and gender), clinical [early morning stiffness (EMS), tenderness in the small joints of the hands] and serological [anti-CCP2 Ab level, third generation anti-CCP Ab (CCP3) and rheumatoid factor (RF)] data were collected at baseline. Regression analyses, Kaplan-Meier analysis and Log-Rank test were performed.

Results:

US synovitis was detected in ≥1 longitudinal US scan in 69/186 (37.1%) at-risk individuals (median time to first developing US synovitis: 53 weeks, IQR 27.0-105.8; median number of joints with US synovitis: 2.0, IQR 1.0-2.0). As shown in Table 1, only anti-CCP3 Ab were significantly associated with development of US sub-clinical synovitis in the multi-variable analysis while borderline results were observed with age.

Table 1.

Regression analyses for the development of US synovitis.

Univariable analysisMultivariableanalysisOR (95% CI)p-valueOR (95% CI)p-valueGender (male)1.02 (0.52-2.02)0.95//Age1.03 (1.01-1.06)<0.011.03 (1.00-1.06)0.03Tenderness in the hands0.86 (0.46-1.61)0.64//EMS1.60 (0.87-2.95)0.13//Anti-CCP2 Ab (high titre)2.79 (1.37-5.67)<0.011.20 (0.50-2.89)0.69Anti-CCP3+4.44 (2.28-8.66)<0.013.30 (1.39-7.89)<0.01RF+2.96 (0.46-1.61)0.011.45 (0.68-3.11)0.33

CCP2+ individuals with positive anti-CCP3 Ab show a significantly reduced sub-clinical synovitis-free survival rate compared with individuals with negative anti-CCP3 Ab (Figure 1). At 1- and 2-year follow-up, respectively 23.3% and 38.3% of individuals with dual CCP2/CCP3 positivity developed sub-clinical synovitis on longitudinal scans, compared with 8.4% and 13.3% of CCP2+ individuals with negative anti-CCP3 Ab (p=0.01) (Figure 1a).

Similar results were observed in the subgroup of high level CCP2+ individuals. At 1- and 2-year follow-up, respectively 24.5% and 39.4% of high level CPP2/anti-CCP3+, but only 6.1% and 15.2% of CCP2+ individuals with negative anti-CCP3 developed sub-clinical synovitis on longitudinal scans (p<0.01) (Figure 1b).

Figure 1.

Kaplan-Meier analysis shows US sub-clinical synovitis free survival time in CCP2+ at-risk individuals.

Conclusion:

In anti-CCP2+ at-risk individuals with MSK symptoms, anti-CCP3 antibodies improve prediction of imminent development of subclinical joint inflammation. This may represent the critical time-point for interventions to prevent the onset of joint disease. This is also a unique population for investigating the drivers of joint involvement in the development of RA.

References:

[1]Duquenne L, et al. The Role of Ultrasound Across the Inflammatory Arthritis Continuum: Focus on “At-Risk” Individuals. 2020.

[2]D’Agostino MA, et al. Scoring ultrasound synovitis in rheumatoid arthritis: a EULAR-OMERACT ultrasound taskforce — Part 1: definition and development of a standardised, consensus-based scoring system. 2017.

Disclosure of Interests:

Andrea Di Matteo Grant/research support from: This study was conducted while Andrea Di Matteo was an ARTICULUM Fellow., Kulveer Mankia Speakers bureau: KM reports personal fees from Abbvie, UCB and Eli Lilly (all <$10.000), outside the submitted work., Grant/research support from: Research grants from BMS, Eli Lilly (all <$10.000), Laurence Duquenne: None declared, Edoardo Cipolletta: None declared, Jacqueline Nam: None declared, Leticia Garcia-Montoya: None declared, Richard Wakefield Speakers bureau: RJW has received honoraria from Abbvie, Novartis and GE for ultrasound related educational activities (all <$10.000)., Michael Mahler Employee of: MM is employee of Inova Diagnostics, commercializing CCP3, Paul Emery Speakers bureau: PE reports consultant fees from BMS, AbbVie, Gilead, Galapagos, Lilly, MSD, Pfizer, Novartis, Roche, and Samsung outside the submitted work (all <$10.000)., Grant/research support from: He also reports research grants from UCB, AbbVie, Lilly, Novartis, BMS, Pfizer, MSD and Roche, outside the submitted work. PE is National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) director and BRC funds supported this work. Leticia Garcia-Montoya and Laurence Duquenne are NIHR BRC fellows.

POS0499 WORK ABSENCE DUE TO MUSCULOSKELETAL SYMPTOMS IN PATIENTS AT-RISK OF RHEUMATOID ARTHRITIS IS COMPARABLE TO THOSE WITH ESTABLISHED DISEASE

Background:

Rheumatoid arthritis (RA) is an established cause of disability and work absence; however, little is known about the impact of musculoskeletal (MSK) symptoms on sick leave in patients at-risk of developing the disease.

Objectives:

To describe the sick leave of individuals at-risk of RA, compared to patients who had recently been diagnosed with RA, over a 12-month period. Additionally, to investigate baseline predictors for sick leave within the first 12 months.

Methods:

A prospective observational cohort for individuals at-risk of RA was conducted. A total of 591 consecutive anti-citrullinated protein antibodie positive (ACPA+) individuals, with no clinical synovitis were recruited. A MSK ultrasound scan and a blood test were performed at baseline, and information about employment regime (retired, not in a paid job, part time and full time), days of sick leave and reasons for absences within the previous months were collected every 3 months and analysed at baseline, 6 months, 12 months and at the moment of diagnosis of an inflammatory arthritis (IA) (if the patient had progressed). Subjects who had retired (n=80) were excluded from the analysis.

A comparison was made with 114 RA patients from an observational study. Employment information was collected at pre-treatment, 6 months and 1 year after diagnosis.

Univariable and logistic regression analyses were performed to assess predictors of work absence due to MSK reasons in the next 12 months from baseline for at-risk individuals.

Results:

Even though the reasons for unemployment were not available, there were no statistically significant differences between employment rates across the timepoints of the study for the at-risk individuals’ group (p=0.778). A similar pattern was observed in the RA patient group; which also maintained the same employment rates throughout the study (p=0.311) and these were comparable to the at-risk individuals’ (p=0.480).

Over 35% of at-risk individuals in paid employment had work absences in the 3 months prior to the baseline visit. Of these 65.5% were due to MSK related issues, meaning 23.2% of the total absences were MSK related. The other reasons for work absence can be seen in table 1. This fell to 12.9% of the total absences at 6 months (which probably reflects clinical intervention) and increased to 38% if the patient progressed to an IA (graph 1).

Table 1.

REASONS FOR SICK LEAVE AT BASELINE IN INDIVIDUALS AT-RISK OF RA (%)

MSK related issues65.5Flu-like symptoms20.1Gastrointestinal issues19.4Stress/anxiety14.4Headaches11.5Infection3.6Fatigue1.4Other3.6

The percentage of individuals who took absence from work due to MSK related issues, was similar in both the at risk and RA group, including an initial reduction possibly due to drug intervention (graph 1). However, the median number of days off work 3 months prior baseline, 6 months and 1 year in RA patients tended to be higher than those in the at-risk group (10, 2 and 6 versus 5, 4 and 3 respectively).

Several factors were assessed to predict sick leave within 12 months in at-risk individuals: age, gender, smoking status, ACPA, rheumatoid factor (RF), anti-nuclear antibodies (ANA), C-reactive protein (CRP), early morning stiffness, shared epitope, joint pain, joint tenderness and abnormal findings in the ultrasound scan (erosions or power doppler); however, only RF [OR 0.18; p=0.018; 95% CI (0.04-0.84)] and CRP [OR 1.3; p=0.021; 95%CI (1.04-1.60)] were statistically significant in the multivariable analysis.

Conclusion:

Even though being at-risk of RA is not considered a potential cause of disability, results show that the burden on the workplace, due to MSK related absences, was comparable to subjects diagnosed with RA. Although further investigation is required, initial data suggests that clinical intervention may reduce this burden; which tends to be higher in at-risk individuals with a negative RF and a high CRP.

Graph 1.

Percentage of individuals who had work absences related to MSK issues 3 months prior to each timepoint.

Acknowledgements:

H. Singh

T. Hulland

G. John

- Leeds Cares -

Disclosure of Interests:

None declared

Unusual Near-Horizon Cosmic-Ray-like Events Observed by ANITA-IV

ANITA's fourth long-duration balloon flight in 2016 detected 29 cosmic-ray (CR)-like events on a background of 0.37_{-0.17}^{+0.27} anthropogenic events. CRs are mainly seen in reflection off the Antarctic ice sheets, creating a phase-inverted waveform polarity. However, four of the below-horizon CR-like events show anomalous noninverted polarity, a p=5.3×10^{-4} chance if due to background. All anomalous events are from locations near the horizon; ANITA-IV observed no steeply upcoming anomalous events similar to the two such events seen in prior flights.

Anti-staphylococcal activity of a cyclic lipopeptide, C15 -bacillomycin D, produced by Bacillus velezensis NST6

AIM

The aim of this study was to assess antibacterial activity of a novel Bacillus velezensis strain NST6, and further identify its active compound against pathogenic Staphylococcus strains for clinical therapeutic applications.

METHODS AND RESULTS

In this study, a novel B. velezensis strain NST6 harbouring strong antimicrobial activity against human pathogenic bacteria was isolated from a soil sample. The solvent extract of the strain exhibited strong antibacterial activity against Gram-positive and Gram-negative bacteria in disc diffusion assay and measurement of minimal inhibitory concentration and bactericidal concentration, of which it showed notable efficacy to Staphylococcus species including Staphylococcus epidermidis, Staphylococcus aureus and methicillin-resistant S. aureus. Strong antibacterial effect against pathogenic S. aureus and low toxicity of the bacterial extract were further validated in Caenorhabditis elegans model. Moreover, by antibacterial activity-guided fractionation using RP-HPLC and LC-MS, we defined C₁₅ -bacillomycin D as the anti-staphylococcal compound produced by the strain.

CONCLUSION

The primary anti-staphylococcal compound from B. velezensis NST6 was identified as a cyclic lipopeptide, C₁₅ -bacillomycin D, which proved its potential to treat Staphylococcus strains in vitro and in vivo experiments with insignificant level of toxicity.

SIGNIFICANCE AND IMPACT OF THE STUDY

We provide an alternative treatment option to Staphylococcus infections by investigating the specific anti-staphylococcal activity of C₁₅ -bacillomycin D produced by a B. velezensis strain.

Comprehensive genomic profiling for non-small-cell lung cancer: health and budget impact

Background

Single-gene tests and hotspot panels targeting specific subsets of biomarkers constitute the Canadian genomic testing landscape for non-small-cell lung cancer (nsclc). However, newer testing options such as comprehensive genomic profiling (cgp) offer improved detection rates and identification of multiple classes of genomic alterations in a single assay, minimizing tissue requirements and turnaround time. The objective of the present analysis was to assess the health and budget impacts of adopting cgp testing for nsclc in Canada.

Methods

This study assessed the impact of funding the cgp tests FoundationOne CDx and FoundationOne Liquid (Foundation Medicine, Cambridge, MA, U.S.A.) over a 3-year time horizon using a Canadian societal perspective for Ontario. Conventional testing strategies were summarized into two reference scenarios: a series of single-gene tests only, and reflex single-gene testing followed by a hotspot panel for negative results. Four adoption scenarios for cgp testing were considered: replacing all single-gene and hotspot panel testing, replacing hotspot panel testing only, use after negative single-gene and hotspot testing, and use of FoundationOne Liquid in individuals with insufficient tissue for conventional testing.

Results

When cgp testing was assumed to replace all conventional testing with 50% uptake, the budget impact per person per year ranged from $0.71 to $0.87, depending on the reference scenario, with a 3-year gain of 680.9 life-years and 3831 working days over the full cohort.

Conclusions

Given the present testing landscape for patients with nsclc in Canada, listing cgp testing could optimize the selection of appropriately targeted treatments, and thus add life-years and productivity for this population, with a minimal budget impact.

OP0112 IN INDIVIDUALS AT RISK OF INFLAMMATORY ARTHRITIS, PATIENT REPORTED OUTCOMES DETERIORATE IN THE 12 WEEKS BEFORE PROGRESSION TO CLINICAL DISEASE

Background:

Subjects with clinically significant arthralgia who will eventually develop inflammatory arthritis (IA) had a higher HAQ at baseline (1). Here we investigated the change in patients reported outcomes (PRO) over time in ACPA+ at risk of IA subjects.

Objectives:

In ACPA+ subjects at risk of developing IA, to analyse the change in PRO results in order to identify an imminent phase of progression.

Methods:

In a single centre prospective observational cohort, PRO from 109 ACPA+ subjects without clinical arthritis were collected prospectively at 0, 12, 26, 39 weeks; the last time-point was 52 weeks for the individuals who did not progress to IA (non-progressors) or the last visit preceding progression (within 12 weeks) for those who developed IA (progressors). Data on the following PRO were collected: HAQ, “general health” (GH-VAS), “fatigue” (fatigue-VAS), and “global pain” (GP-VAS) using visual analogic scale measures graded 0 to 100. We firstly used mixed models repeated measures ANOVA analysis then included covariates such as gender, shared epitope (SE) (HLA DRB1*01, *04 and/or *10), anti-CCP2 antibody (CCP2) and/or rheumatoid factor (RF) high titre (≥3ULN), and smoking exposure (Ever/Never).

Results:

All analysis met sphericity assumption. In this selection, 20% of subjects (24/109) developed IA within a median of 77 weeks (Range 37-369.43), non-progressors were followed for a median of 216 weeks (Range 50-590), 74 subjects were SE positive (68%), 81 had a CCP2 and/or RF high titre (74%), and 66 were previous or current smokers (61%).

Analysis revealed significant differences between both groups for the last visit, and within the progressor group for the last visit compared to all previous visits regarding the GH-VAS, GP-VAS and HAQ (Table 1, figure 1). Between subject analysis showed a significant influence of GH-VAS and GP-VAS change on progression. Covariate analysis showed a significant influence of previous smoking history on HAQ results (p=0.033, F=2.645 (4,408), Eta = 0.025).

Table 1.

Mixed Models repeated measures

General HealthGlobal PainHAQFatigueWithin subject effects;VAS change over time depending on group.P= 0.004F(4, 428) = 3.883Partial Eta Square= 0.35P < 0.001F(4, 400) = 5.754Partial Eta Squared = 0.054P = 0.115P = 0.459Pairwise comparison within groupNon-progressors:all p > 0.05Non-progressors:all p > 0.05Non-progressors:all p > 0.05Non-progressors:all p > 0.05Progressors:Time-point 1 to 5:p = 0.010SE = 4.199Time-point 2 to 5:p = 0.001SE = 4.709Time-point 3 to 5:P = 0.001SE = 3.842Time-point 4 to 5:P = 0.043SE = 4.239Progressors:Time-point 1 to 5:p < 0.001SE = 6.172Time-point 2 to 5:p < 0.001SE = 5.518Time-point 3 to 5:P = 0.002SE = 5.246Time-point 4 to 5:P = 0.001SE = 5.333Progressors:Time-point 1 to 5:p = 0.215Time-point 2 to 5:P = 0.036SE = 0.068Time-point 3 to 5:P = 0.040SE = 0.062Time-point 4 to 5:P = 0.017SE = 0.066Progressors:Time-point 1 to 5:p = 0.448Time-point 2 to 5:P =0.292Time-point 3 to 5:P = 0.047SE = 5.421Time-point 4 to 5:P = 0.202Pairwise comparison between groupLast visit:P = 0.009SE = 5.454All other visits:P > 0.05Last visit:P = 0.003SE = 7.082All other visits:P > 0.05Last visit:P = 0.016SE = 0.119All other visits:P > 0.05P-value > 0.05Mauchly’s test of sphericityP = 0.099P = 0.050P = 0.057P = 0.722N (Progressors/total)24/10915/10224/10719/102Figure 1.

Repeated measure ANOVA between groups

Conclusion:

These results show for the first time a significant deterioration in the PRO of general health, global pain, and HAQ weeks just preceding clinical arthritis development. This phase prior progression needs to be thoroughly studied to improve the accuracy of predicting imminent progression.

References:

[1]Ten Brinck RM et al. Functional limitations in the phase of clinically suspect arthralgia are as serious as in early clinical arthritis; a longitudinal study. RMD open. 2017;3(1):e000419.

Disclosure of Interests:

Laurence Duquenne: None declared, Kulveer Mankia: None declared, Leticia Garcia-Montoya: None declared, Jacqueline Nam: None declared, Andrea Di Matteo Grant/research support from: the publication was conducted while Dr. Di Matteo was an ARTICULUM fellow, Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor)

FRI0036 VALIDATION OF RISK SCORES FOR PREDICTING PROGRESSION IN INDIVIDUALS “AT RISK OF RHEUMATOID ARTHRITIS”

Background:

Composite scores for risk of progression were described in 2015 in a cohort of 100 anti-cyclic citrullinated peptide (anti-CCP) + individuals at risk of developing Inflammatory Arthritis (IA) (1). The first score, designed for primary care, was based on anti-CCP and rheumatoid factor (RF) titres, small joints tenderness and early morning stiffness (EMS). A second score developed for secondary care added power Doppler presence (PD+) and/or at least one allele positive for the shared epitope (SE+).

Objectives:

To validate previous data by scoring risk factors in a new cohort of 394 individuals.

Methods:

Individuals at risk of developing IA selected by a positive anti-CCP test and a new musculoskeletal symptom have been followed in a single-centre prospective observational cohort since 2008. The previous risk score was derived from 100 patients. With the same recruitment and follow-up pathways, the next 394 consecutive participants were studied (full data were available for 373 patients for secondary care model). Participants followed for less than 10 weeks without progression were excluded.

Results:

Participants from both cohorts were similar in terms of age and sex. Although the mean time to progression is comparable, there were significantly more participants with a high titre anti-CCP test in the 2015 cohort (Table 1).

Table 1.

Patients characteristics

Score20152020N100394Percentage of progression n/N50/100 (50%)82/413 (19.9%)Mean of follow-up before progression to IA (Months (SD))15.35 (15.27)13.50 (12.62)Mean follow-up of non progressors (Months (SD))39.7 (15.82)27.6 (19.75)Mean follow-up duration: all participants (Months (SD))27.7(19.36)24.8 (19.38)High CCP titre83%65%Women72%72%Smoker ever72%50%Age (Mean (SD))51.2 (11.9)50.2 (13.474)

Cox multivariable analysis showed similar Hazard Ratios (HR) of progression in both groups (Table 2) confirming the high predictive value of high CCP/RF titre, early morning stiffness duration, power doppler presence and shared epitope. High risk of progression individuals identified by the secondary score were eight times more likely to develop IA (HR = 8.290, CI = 3.763-18.264, p<0.001), 50% of them had progressed at 2 years (Figure 1).

Table 2.

Multivariable Cox regression analysis of time to progression to inflammatory arthritis.

2015 (n=98)2020 (n=394)Primary care modelHRp-valueCIHRp-valueCIHigh anti-CCP or RF titre4.860.0311.16−20.434.96<0.0011.445−3.526EMS≥30min1.860.0391.03−3.372.26<0.0011.445−3.526Small Joints Tenderness1.420.2520.78−2.571.300.2490.832−2.0352015 (n=98)2020 (n=373)Secondary care modelHRp-valueCIHRp-valueCIHigh anti-CCP or RF titre3.040.1470.68−13.63.920.0011.790−8.567EMS≥30min1.560.1670.83−2.922.100.0021.314−3.357Small Joints Tenderness1.540.1780.82−2.881.340.2160.843−2.135PD signal1.920.0331.06−3.502.350.0011.424−3.887Shared epitope1.570.2720.70−3.492.330.0031.333−4.059Figure 1.

Probability of IA free survival according to categories of risk in the secondary care model.

Conclusion:

These data from a new large cohort confirm the validity previous Leeds Risk Scores for Primary and Secondary care, and the fidelity of the risk factors over time to predict progression.

References:

[1]Rakieh C, Nam JL, Hunt L, Hensor EM, Das S, Bissell LA, et al. Predicting the development of clinical arthritis in anti-CCP positive individuals with non-specific musculoskeletal symptoms: a prospective observational cohort study. Annals of the rheumatic diseases. 2015;74(9):1659-66.

Disclosure of Interests:

Laurence Duquenne: None declared, Jacqueline Nam: None declared, Kulveer Mankia: None declared, Leticia Garcia-Montoya: None declared, Andrea Di Matteo Grant/research support from: the publication was conducted while Dr. Di Matteo was an ARTICULUM fellow, Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor)

FRI0557 IN INDIVIDUALS AT-RISK OF RHEUMATOID ARTHRITIS, ULTRASOUND BONE EROSIONS AT THE V METATARSOPHALANGEAL JOINTS ARE THE MOST PREDICTIVE FOR THE DEVELOPMENT OF CLINICAL ARTHRITIS

Background:

While the central role of bone erosions in the pathogenesis and diagnosis of patients with rheumatoid arthritis (RA) is widely recognized, their prevalence, pattern, and relationship with subclinical synovitis in individuals at-risk of RA (positive autoantibodies without clinical arthritis) is not well understood.

Objectives:

To investigate, in individuals at-risk of RA, the prevalence and distribution of ultrasound (US) bone erosions, their correlation with subclinical synovitis at joint level, and their association with the development of inflammatory arthritis (IA).

Methods:

Baseline US scans of 2ndgeneration anti-cyclic citrullinated peptide (CCP) positive at-risk subjects with musculoskeletal symptoms (without clinical arthritis) taking part in the Leeds CCP study were analyzed. The presence of bone erosions was evaluated in the classic sites for RA damage: the II and V metacarpophalangeal (MCP) joints, and the V metatarsophalangeal (MTP) joints1. US synovitis was defined as synovial hypertrophy (SH) ≥2 or SH ≥1 + power Doppler signal ≥12. Only subjects with ≥1 follow-up visit were included in the progression analysis (n=400). Progression to IA was defined as the development of clinical synovitis in ≥1 one joint.

Results:

US bone erosions: prevalence, distribution, and association with subclinical synovitis

A total of 2514 joints, in 419 subjects were evaluated.

Bone erosions were found in ≥1 joint in 41/419 subjects (9.8%), in 55/2514 joints (2.2%). The prevalence of bone erosions was significantly higher in the V MTP than in the MCP joints (p<0.01). They were detected in 42 V MTP (31 subjects; 7.4%), in 10 II MCP (10 subjects; 2.4%), and in 3 V MCP (3 subjects; 0.7%) joints. US synovitis was detected in 22/55 joints (40%) with bone erosions, in 17/41 subjects (42%). It was found in 48.6% of the V MTP, in 20% of the II MCP and in none of the V MCP joints with bone erosions. A significant correlation between bone erosions and synovitis in the same joint was detected (Cramer’s V=0.22, p<0.01).

Seven out of the 55 joints (12.7%) with bone erosions were tender on physical examination: 14.3% of the V MTP, 10% of the II MCP, and none of the V MCP joints.

US bone erosions: predicting development of IA

A total of 122 subjects (30.5%) developed IA (median follow-up: 301 days, IQR 112-721). The hazard ratios of the US findings for the development of IA (adjusted for age, sex, smoking, anti-CCP and rheumatoid factor titer) are reported in Table 1.

Table 1.EverAt 1 yearAt 3 yearsHR (95%CI)P valueHR (95%CI)P valueHR (95%CI)P valuePresence of bone erosion in ≥1 joint (any joint)3.98(1.82-8.7)<0.013.57(1.7-7.5)<0.013.48(1.63-7.4)<0.01- in the II MCP joints2.4(0.52-11.08)0.261.07(0.2-5.76)0.941.67(0.38-7.04)0.5- in the V MCP joints1.37(0.06-31)0.850(N/A)10(N/A)1- in the V MTP joints4.79(1.97-11.63)<0.015.23(2.32-11.8)<0.015.43(2.28-12.92)<0.01Presence of bone erosion and synovitis in the same joint (any joint)3.9(1.19-12.77)0.026.03(2.07-17.55)<0.013.91(1.29-11.85)0.02Presence of bone erosion and synovitis in the same V MTP joint5.08(1.37-18.9)0.027.03(2.28-21.71)<0.014.89(1.48-16.19)<0.01Presence of bone erosion in >1 joint (any joint)10.63(1.87-60.42)<0.015.68(1.66-19.5)<0.017.26(1.67-31.66)<0.01

IA free survival rates are showed in Figures 1 and 2.

Figure 1.Figure 2.

Conclusion:

The feet appear to be an early site for damage in individuals at-risk of RA. US bone erosions were mainly detected in asymptomatic joints, but frequently in association with subclinical synovitis. In individuals at-risk of RA, bone erosions in the V MTP joints are more predictive than in the hands (II and V MCP joints) for the development of IA.

References:

[1] Zayat AS, et al. Ann Rheum Dis. 2015;

[2] D’Agostino, et al. RMD Open. 2017;

Disclosure of Interests:

Andrea Di Matteo Grant/research support from: the publication was conducted while Dr. Di Matteo was an ARTICULUM fellow, Kulveer Mankia: None declared, Laurence Duquenne: None declared, Edoardo Cipolletta: None declared, Richard Wakefield Speakers bureau: Novartis, Janssen, GE, Jacqueline Nam: None declared, Leticia Garcia-Montoya: None declared, Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor)

THU0558 ANTI-CCP NEGATIVE PATIENTS WITH NEW MUSCULOSKELETAL SYMPTOMS: IMPROVING REFERRALS FROM PRIMARY CARE

Background:

The presence of anti-cyclic citrullinated peptide antibodies (anti-CCP antibodies) is associated with progression to inflammatory arthritis (IA) [1]; however, most patients attending primary care with a new non-specific musculoskeletal (MSK) complaint and no clinical synovitis have a negative result for this test (CCP-). Considering that only a small proportion of these individuals will be diagnosed with an IA within the next 12 months, predicting disease progression in these patients appears to be more challenging.

Objectives:

To investigate factors that could be associated with disease progression in patients testing CCP- in order to optimise primary care referrals to Rheumatology.

Methods:

A prospective observational study recruiting patients over 16 years old with a new MSK complaint and no clinical synovitis was conducted. Patients recruited from primary care centres across the UK from July 2007 until November 2018 were included in this analysis. Those testing negative for the anti-CCP2 assay (initially phadia, later bioplex) were sent questionnaires 1 year later, and GPs were contacted in November 2019 to confirm their disease status.

Results:

7521 eligible patients were recruited from primary care. 7290 (97%) of them were CCP- and 5678 returned the questionnaire after 1 year. 239 patients (4.2%) of these CCP- reported progression to IA; however, this diagnosis was only confirmed in 53 of them (0.93%). In another 38 patients, the IA diagnosis could not be confirmed and therefore they were not included in the analysis. 21 patients progressed to rheumatoid arthritis (RA), 13 to spondyloarthritis, 11 to polymyalgia rheumatica (requiring disease-modifying anti-rheumatic drugs), 3 to polymyositis, 3 to systemic lupus erythematosus and 2 to systemic sclerosis. Table 1 describes the most troublesome joints and table 2 other concomitant MSK diagnoses of the non-progressors/ progressors; and among the last ones, the RA group. Multivariable analysis showed that pain in specific joints was associated with development of IA within the following 12 months: hand odds ratio (OR) 2.1 [95%CI (1.09-4.16), p=0.027], knee OR 2.0 [95%CI (1.13-3.91), p=0.02], and shoulder OR 1.8 [95%CI (1.02-3.45), p=0.043). Smoking exposure, having a first degree relative with RA and gender were not predictive for progression. Older age showed only a slightly higher risk for IA [OR 1.04, 95%CI (1.01-1.06) p=0.001].

Table 1.

Characteristics, troublesome joints of the participants

NON-PROGRESSORS(n=5588)PROGRESSORS (n=52)RA progressors (n=21)Carpal tunnel syndrome%131730Rotator cuff %121920Trigger finger %540Tennis elbow %15105Osteoarthritis %182520Table 2.

Concomitant MSK diagnosis

NON-PROGRESSORS(n=5588)PROGRESSORS (n=52)RA progressors (n=21)Female %725857Mean age y.o.53 (16-91)60 (30-82)60 (30-82)FDR with RA %383333Ever Smoked %384340Neck pain %302914Shoulder pain %415852Elbow pain %293829Wrist pain %384648Hand pain %537176Thumb pain %364857Back pain %332524Hip pain %362919Knee pain %557162Ankle pain %302324Foot pain %344033

Conclusion:

In CCP- patients without clinical synovitis, hand, knee and shoulder pain should be investigated more carefully as these involve a higher risk of progression to IA. Patient reported outcomes regarding rheumatic diseases are not reliable; the distribution of joint pain seems to be a more useful tool than the family history when assessing the need for referral to Rheumatology.

References:

[1]Rakieh C. Ann Rheum Dis. 2015;74:1659-66

Acknowledgments:

National Institute of Health Research (NIHR)

Leeds Biomedical Research Centre (BRC)

Disclosure of Interests:

Leticia Garcia-Montoya: None declared, Jacqueline Nam: None declared, Kulveer Mankia: None declared, Laurence Duquenne: None declared, Andrea Di Matteo Grant/research support from: the publication was conducted while Dr. Di Matteo was an ARTICULUM fellow, Paul Emery Grant/research support from: AbbVie, Bristol-Myers Squibb, Merck Sharp & Dohme, Pfizer, Roche (all paid to employer), Consultant of: AbbVie (consultant, clinical trials, advisor), Bristol-Myers Squibb (consultant, clinical trials, advisor), Lilly (clinical trials, advisor), Merck Sharp & Dohme (consultant, clinical trials, advisor), Novartis (consultant, clinical trials, advisor), Pfizer (consultant, clinical trials, advisor), Roche (consultant, clinical trials, advisor), Samsung (clinical trials, advisor), Sandoz (clinical trials, advisor), UCB (consultant, clinical trials, advisor)

Observation of Radar Echoes from High-Energy Particle Cascades

We report the observation of radar echoes from the ionization trails of high-energy particle cascades. Data were taken at the SLAC National Accelerator Laboratory, where the full electron beam (∼10^{9}  e^{-} at ∼10  GeV/e^{-}) was directed into a plastic target to simulate an ultrahigh-energy neutrino interaction. The target was interrogated with radio waves, and coherent radio reflections from the cascades were detected with properties consistent with theoretical expectations. This is the first definitive observation of radar echoes from high-energy particle cascades, which may lead to a viable neutrino detection technology for energies ≳10^{16}  eV.

Single GaAs Nanowire/Graphene Hybrid Devices Fabricated by a Position-Controlled Microtransfer and an Imprinting Technique for an Embedded Structure

We developed a new technique to fabricate single nanowire devices with reliable graphene/nanowire contacts using a position-controlled microtransfer and an embedded nanowire structure in a planar junction configuration. A thorough study of electrical properties and fabrication challenges of single p-GaAs nanowire/graphene devices was carried out in two different device configurations: (1) a graphene bottom-contact device where the nanowire-graphene contact junction is formed by transferring a nanowire on top of graphene and (2) a graphene top-contact device where the nanowire-graphene contact junction is formed by transferring graphene on top of an embedded nanowire. For the graphene top-contact devices, graphene-nanowire-metal devices, where graphene is used as one electrode and metal is the other electrode to a nanowire, and graphene-nanowire-graphene devices, where both electrodes to a nanowire are graphene, were investigated and compared with conventional metal/p-GaAs nanowire devices. Conventional metal/p-GaAs nanowire contact devices were further investigated in embedded and nonembedded nanowire device configurations. A significantly improved current in the embedded device configuration is explained with a "parallel resistors model" where the high-resistance parts with the metal-semiconductor Schottky contact and the low-resistance parts with noncontacted facets of the hexagonal nanowires are taken into consideration. Consistently, the nonembedded nanowire structure is found to be depleted much easier than the embedded nanowires from which an estimation for a fully depleted condition has also been established.

Observation of an Unusual Upward-Going Cosmic-Ray-like Event in the Third Flight of ANITA

We report on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third flight of the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload, is consistent with a similar event reported in a previous flight. These events could be produced by the atmospheric decay of an upward-propagating τ lepton produced by a ν_{τ} interaction, although their relatively steep arrival angles create tension with the standard model neutrino cross section. Each of the two events have a posteriori background estimates of ≲10^{-2} events. If these are generated by τ-lepton decay, then either the charged-current ν_{τ} cross section is suppressed at EeV energies, or the events arise at moments when the peak flux of a transient neutrino source was much larger than the typical expected cosmogenic background neutrinos.

Transformative piezoelectric enhancement of P(VDF-TrFE) synergistically driven by nanoscale dimensional reduction and thermal treatment

Despite the significant potential of organic piezoelectric materials in the electro-mechanical or mechano-electrical applications that require light and flexible material properties, the intrinsically low piezoelectric performance as compared to traditional inorganic materials has limited their full utilization. In this study, we demonstrate that dimensional reduction of poly(vinylidene fluoride trifluoroethylene) (P(VDF-TrFE)) at the nanoscale by electrospinning, combined with an appropriate thermal treatment, induces a transformative enhancement in piezoelectric performance. Specifically, the piezoelectric coefficient (d₃₃) reached up to -108 pm V^-1, approaching that of inorganic counterparts. Electrospun mats composed of thermo-treated 30 nm nanofibers with a thickness of 15 μm produced a consistent peak-to-peak voltage of 38.5 V and a power output of 74.1 μW at a strain of 0.26% while sustaining energy production over 10k repeated actuations. The exceptional piezoelectric performance was realized by the enhancement of piezoelectric dipole alignment and the materialization of flexoelectricity, both from the synergistic effects of dimensional reduction and thermal treatment. Our findings suggest that dimensionally controlled and thermally treated electrospun P(VDF-TrFE) nanofibers provide an opportunity to exploit their flexibility and durability for mechanically challenging applications while matching the piezoelectric performance of brittle, inorganic piezoelectric materials.

Crystal growth and piezoelectric characterization of mechanically stable ZnO nanostructure arrays

The highest piezoelectric performance of ZnO can be achieved by utilizing the piezoelectric operation along the c-axis due to its anisotropic permanent dipole moment.

Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites

The topotactic phase transition in SrCoO_x (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO_2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO₃ that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO_2.5, however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoO_x is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.

The subgingival microbiomes in periodontitis and health of individuals with rheumatoid arthritis and at risk of developing rheumatoid arthritis

Serum anti-citrullinated protein antibodies (ACPAs), present in 70% of people with rheumatoid arthritis (RA), can be detected ≤10years before the onset of clinical disease. RA and periodontitis are epidemiologically associated and we have reported a high incidence of periodontitis in people who are ACPA+ and at risk of RA. Periodontal bacteria may contribute by multiple routes to the generation of RA-autoantibodies. This study aims to characterise the subgingival microbiomes from periodontitis and health in individuals with/without RA and at risk of RA.

Forty-five ACPA+ no RA (RA-at-risk; RAR), 31 healthy controls (HC) and 30 ACPA+ RA patients (RA) underwent a periodontal examination. DNA from subgingival plaque from healthy and deep pocket sites were paired-end sequenced using the Illumina HiSeq3000 and data analysed using MG-RAST + DESeq.

Metagenomes in RA samples had high proportions of Actinobacteria; RAR microbiomes contained higher proportions of Bacteroidetes than HC. The relative abundance of P. gingivalis was high in periodontitis and RAR; Aggregatibacter actinomycetemcomitans was detected with similar frequency in each group. Other bacteria implicated in periodontitis and/or autoantibody generation (Filifactor alocis, Prevotella spp, Leptotrichia spp.) were detected. Analyses are on-going to elucidate the diversity and functional potential of the subgingival microbiome associated with RA.

GABA-B Agonist Baclofen Normalizes Auditory-Evoked Neural Oscillations and Behavioral Deficits in the Fmr1 Knockout Mouse Model of Fragile X Syndrome

Fragile X syndrome is a genetic condition resulting from FMR1 gene mutation that leads to intellectual disability, autism-like symptoms, and sensory hypersensitivity. Arbaclofen, a GABA-B agonist, has shown efficacy in some individuals with FXS but has become unavailable after unsuccessful clinical trials, prompting interest in publicly available, racemic baclofen. The present study investigated whether racemic baclofen can remediate abnormalities of neural circuit function, sensory processing, and behavior in Fmr1 knockout mice, a rodent model of fragile X syndrome. Fmr1 knockout mice showed increased baseline and auditory-evoked high-frequency gamma (30-80 Hz) power relative to C57BL/6 controls, as measured by electroencephalography. These deficits were accompanied by decreased T maze spontaneous alternation, decreased social interactions, and increased open field center time, suggestive of diminished working memory, sociability, and anxiety-like behavior, respectively. Abnormal auditory-evoked gamma oscillations, working memory, and anxiety-related behavior were normalized by treatment with baclofen, but impaired sociability was not. Improvements in working memory were evident predominantly in mice whose auditory-evoked gamma oscillations were dampened by baclofen. These findings suggest that racemic baclofen may be useful for targeting sensory and cognitive disturbances in fragile X syndrome.

Characteristics of Four Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

We report on four radio-detected cosmic-ray (CR) or CR-like events observed with the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload. Two of the four were previously identified as stratospheric CR air showers during the ANITA-I flight. A third stratospheric CR was detected during the ANITA-II flight. Here, we report on characteristics of these three unusual CR events, which develop nearly horizontally, 20-30 km above the surface of Earth. In addition, we report on a fourth steeply upward-pointing ANITA-I CR-like radio event which has characteristics consistent with a primary that emerged from the surface of the ice. This suggests a possible τ-lepton decay as the origin of this event, but such an interpretation would require significant suppression of the standard model τ-neutrino cross section.

Accelerator Measurements of Magnetically Induced Radio Emission from Particle Cascades with Applications to Cosmic-Ray Air Showers

For 50 years, cosmic-ray air showers have been detected by their radio emission. We present the first laboratory measurements that validate electrodynamics simulations used in air shower modeling. An experiment at SLAC provides a beam test of radio-frequency (rf) radiation from charged particle cascades in the presence of a magnetic field, a model system of a cosmic-ray air shower. This experiment provides a suite of controlled laboratory measurements to compare to particle-level simulations of rf emission, which are relied upon in ultrahigh-energy cosmic-ray air shower detection. We compare simulations to data for intensity, linearity with magnetic field, angular distribution, polarization, and spectral content. In particular, we confirm modern predictions that the magnetically induced emission in a dielectric forms a cone that peaks at the Cherenkov angle and show that the simulations reproduce the data within systematic uncertainties.

T cell subsets: an immunological biomarker to predict progression to clinical arthritis in ACPA-positive individuals

Objectives

Anticitrullinated protein antibody (ACPA)+ individuals with non-specific musculoskeletal symptoms are at risk of inflammatory arthritis (IA). This study aims to demonstrate the predictive value of T cell subset quantification for progression towards IA and compare it with previously identified clinical predictors of progression.

Methods

103 ACPA+ individuals without clinical synovitis were observed 3-monthly for 12 months and then as clinically indicated. The end point was the development of IA. Naïve, regulatory T cells (Treg) and inflammation related cells (IRCs) were quantified by flow cytometry. Areas under the ROC curve (AUC) were calculated. Adjusted logistic regressions and Cox proportional hazards models for time to progression to IA were constructed.

Results

Compared with healthy controls (age adjusted where appropriate), ACPA+ individuals demonstrated reduced naïve (22.1% of subjects) and Treg (35.8%) frequencies and elevated IRC (29.5%). Of the 103 subjects, 48(46.6%) progressed. Individually, T cell subsets were weakly predictive (AUC between 0.63 and 0.66), although the presence of 2 T cell abnormalities had high specificity. Three models were compared: model-1 used T cell subsets only, model-2 used previously published clinical parameters, model-3 combined clinical data and T cell data. Model-3 performed the best (AUC 0.79 (95% CI 0.70 to 0.89)) compared with model-1 (0.75 (0.65 to 0.86)) and particularly with model-2 (0.62 (0.54 to 0.76)) demonstrating the added value of T cell subsets. Time to progression differed significantly between high-risk, moderate-risk and low-risk groups from model-3 (p=0.001, median 15.4 months, 25.8 months and 63.4 months, respectively).

Conclusions

T cell subset dysregulation in ACPA+ individuals predates the onset of IA, predicts the risk and faster progression to IA, with added value over previously published clinical predictors of progression.

Follistatin-like 3 is a mediator of exercise-driven bone formation and strengthening

Exercise is vital for maintaining bone strength and architecture. Follistatin-like 3 (FSTL3), a member of follistatin family, is a mechanosensitive protein upregulated in response to exercise and is involved in regulating musculoskeletal health. Here, we investigated the potential role of FSTL3 in exercise-driven bone remodeling. Exercise-dependent regulation of bone structure and functions was compared in mice with global Fstl3 gene deletion (Fstl3-/-) and their age-matched Fstl3+/+ littermates. Mice were exercised by low-intensity treadmill walking. The mechanical properties and mineralization were determined by μCT, three-point bending test and sequential incorporation of calcein and alizarin complexone. ELISA, Western-blot analysis and qRT-PCR were used to analyze the regulation of FSTL3 and associated molecules in the serum specimens and tissues. Daily exercise significantly increased circulating FSTL3 levels in mice, rats and humans. Compared to age-matched littermates, Fstl3-/- mice exhibited significantly lower fracture tolerance, having greater stiffness, but lower strain at fracture and yield energy. Furthermore, increased levels of circulating FSTL3 in young mice paralleled greater strain at fracture compared to the lower levels of FSTL3 in older mice. More significantly, Fstl3-/- mice exhibited loss of mechanosensitivity and irresponsiveness to exercise-dependent bone formation as compared to their Fstl3+/+ littermates. In addition, FSTL3 gene deletion resulted in loss of exercise-dependent sclerostin regulation in osteocytes and osteoblasts, as compared to Fstl3+/+ osteocytes and osteoblasts, in vivo and in vitro. The data identify FSTL3 as a critical mediator of exercise-dependent bone formation and strengthening and point to its potential role in bone health and in musculoskeletal diseases.

Temperature-dependent resonance energy transfer from semiconductor quantum wells to graphene

Resonance energy transfer (RET) has been employed for interpreting the energy interaction of graphene combined with semiconductor materials such as nanoparticles and quantum-well (QW) heterostructures. Especially, for the application of graphene as a transparent electrode for semiconductor light emitting diodes, the mechanism of exciton recombination processes such as RET in graphene-semiconductor QW heterojunctions should be understood clearly. Here, we characterized the temperature-dependent RET behaviors in graphene/semiconductor QW heterostructures. We then observed the tuning of the RET efficiency from 5% to 30% in graphene/QW heterostructures with ∼60 nm dipole-dipole coupled distance at temperatures of 300 to 10 K. This survey allows us to identify the roles of localized and free excitons in the RET process from the QWs to graphene as a function of temperature.

Stable and reversible doping of graphene by using KNO3 solution and photo-desorption current response

We found stable n-type doping and carrier mobility improvement of graphene by using KNO₃ solution and investigated photo-desorption current response.

The synthesis of organic charge transfer hetero-microtubules by crack welding

The strain-induced cracks in organic microtubules composed of an organic charge transfer (CT) complex of 1,2,4,5-tetracyanobenzene (TCNB) and naphthalene were selectively welded via the formation of secondary CT complexes; this process, in turn, led to the formation of organic hetero-microtubules consisting of multiple segments of two organic CT complexes.