Surface doping of rubrene single crystals by molecular electron donors and acceptors

The surface molecular doping of organic semiconductors can play an important role in the development of organic electronic or optoelectronic devices. Single-crystal rubrene remains a leading molecular candidate for applications in electronics due to its high hole mobility. In parallel, intensive research into the fabrication of flexible organic electronics requires the careful design of functional interfaces to enable optimal device characteristics. To this end, the present work seeks to understand the effect of surface molecular doping on the electronic band structure of rubrene single crystals. Our angle-resolved photoemission measurements reveal that the Fermi level moves in the band gap of rubrene depending on the direction of surface electron-transfer reactions with the molecular dopants, yet the valence band dispersion remains essentially unperturbed. This indicates that surface electron-transfer doping of a molecular single crystal can effectively modify the near-surface charge density, while retaining good charge-carrier mobility.

Soli-enabled noncontact heart rate detection for sleep and meditation tracking

Heart rate (HR) is a crucial physiological signal that can be used to monitor health and fitness. Traditional methods for measuring HR require wearable devices, which can be inconvenient or uncomfortable, especially during sleep and meditation. Noncontact HR detection methods employing microwave radar can be a promising alternative. However, the existing approaches in the literature usually use high-gain antennas and require the sensor to face the user's chest or back, making them difficult to integrate into a portable device and unsuitable for sleep and meditation tracking applications. This study presents a novel approach for noncontact HR detection using a miniaturized Soli radar chip embedded in a portable device (Google Nest Hub). The chip has a [Formula: see text] dimension and can be easily integrated into various devices. The proposed approach utilizes advanced signal processing and machine learning techniques to extract HRs from radar signals. The approach is validated on a sleep dataset (62 users, 498 h) and a meditation dataset (114 users, 1131 min). The approach achieves a mean absolute error (MAE) of 1.69 bpm and a mean absolute percentage error (MAPE) of [Formula: see text] on the sleep dataset. On the meditation dataset, the approach achieves an MAE of 1.05 bpm and a MAPE of [Formula: see text]. The recall rates for the two datasets are [Formula: see text] and [Formula: see text], respectively. This study represents the first application of the noncontact HR detection technology to sleep and meditation tracking, offering a promising alternative to wearable devices for HR monitoring during sleep and meditation.

Quantitative and Qualitative Impact of CT-Based Radiotherapy Dose Maps on Radiologists' Interpretation of Post-treatment Thoracic Surveillance Imaging

PURPOSE/OBJECTIVE(S)

For diagnostic radiologists, interpretation of surveillance imaging for oncology patients treated with radiation therapy (RT) can be challenging because (1) the imaging order may not adequately describe the radiation fields and (2) RT treatment effect and progression can appear similar. Volumetric dose visualization used for plan review is often inaccessible to radiologists. We hypothesize that displaying RT dose would improve radiologists' confidence and ability to correctly identify and distinguish irradiated targets and treatment effects.

MATERIALS/METHODS

CT images were read by a board-certified cardiothoracic radiologist and a diagnostic radiology resident. The readers interpreted pre-RT, treatment planning, and 3-4 month post-RT CT images in anonymized software sessions first without, then-after a 1 month "washout" period-with access to RT dose overlay. Six color-coded isodose lines ranging from 25% to 110% represented in absolute cGy were displayed along with a brief clinical history. RT fractionation schedules ranged in BED10 from 39 to 112.5 Gy. Readers were asked to label the treated lesion(s) and treatment effect(s), and record their confidence using a Likert scale of 1-5 and agreement with statements using yes/no responses.

RESULTS

Two readersindependently interpreted imaging for 32 patients who received thoracic RT to 1-5 lesion(s) for primary (24) or metastatic (8) cancer. Nineteen patients had 1 lesion and 13 patients had >1 lesion. Correct identification of all treated lesions significantly increased with the addition of dose visualization (61% to 81%; McNemar test, p = 0.00079), with the largest increase noted for cases with >1 lesion (15% to 54%; McNemar test, p = 0.0039). With the addition of dose information, the number of false negatives attributable to missed extranodal targets fell from 52% to 18%. Without dose information, 13% of labeled lesions and treatment effects fell outside of the 25% isodose lines, representing false positives. With the addition of dose information, false positives fell below 2% for both lesions and treatment effects. The readers' confidence that they had identified treated lesion(s) increased from a rating of 4.1 to 4.8 on a scale of 1-5 (Paired two-tail t test; p = 0.000005).

CONCLUSION

Whendiagnostic radiologists have access to dose visualization, correct identification rate of irradiated lesions and treatment effects, as well as confidence in these identifications significantly increased. The decrease in false negatives could reduce potential missed identification of tumor progression while the decrease in false positives could reduce inaccurate identification of treatment failure in a new or stable lesion. Our results demonstrate that adding volumetric visualization of dose to imaging could improve quality of surveillance care for patients with irradiated thoracic malignancies.

Prevalence of modifiable risk factors and related poor cardiovascular outcomes following atrial fibrillation ablation

Background

Atrial fibrillation (AF) has become a global epidemic. Early catheter ablation and therapies modifying risk factors (RF) have been shown to improve outcomes of AF ablation. However, the time invested in pursuing risk factor modification may delay ablation, which could negate the procedural benefit.

Purpose

This study sought to investigate the prevalence and impact of potentially modifiable RF among AF patients undergoing catheter ablation in clinical practice.

Methods

This retrospective study included 724 consecutive patients undergoing AF ablation at a tertiary care center from 2012–2019. Pre-specified modifiable risks were examined, including the time from AF diagnosis to ablation, fluctuation/increase in BMI >5% prior to ablation, mean systolic/diastolic blood pressure >125/80 mmHg, obstructive sleep apnea with CPAP noncompliance, hyperlipidemia without statin therapy, tobacco use, excessive alcohol use, and diabetes mellitus with hemoglobin A1c (HbA1c) >6.5%. The primary outcome was a composite of recurrent atrial arrhythmias, cardiovascular (CV) hospitalizations and mortality following AF ablation. A multivariate analysis was performed.

Results

The mean age was 61±10 years old, 32.5% were female and 72.2% had persistent AF. Many study patients had modifiable RF, ranging from 4.7% with excessive alcohol use to 64.0% experiencing delayed AF ablation. The mean time from AF diagnosis to ablation was 4.7 years. During a mean follow-up of 1.6 years after ablation, 467 (64.5%) patients met the primary outcome. Independent RF for the primary outcome were an increase/fluctuation in BMI >5% (adjusted hazard ratio [AHR] 1.31, 95% confidence interval [CI] 1.07–1.60; P=0.008), diabetes with HbA1c >6.5% (AHR 1.50, 95% CI 1.09–2.03; P=0.014) and hyperlipidemia without statin therapy (AHR 1.30, 95% CI 1.08–1.57; P=0.005). Delayed AF ablation over 1.5 years did not alter the outcome, Figure 1.

Conclusion

Substantial portions of patients undergoing AF ablation have potentially modifiable RF. Increased or fluctuating BMI, diabetes with HbA1c >6.5%, and hyperlipidemia not treated with statin therapy portend an increased risk of recurrent atrial arrhythmia, CV hospitalizations and mortality. These findings underscore an importance pursuing RF management in patients with AF to reduce adverse outcomes after ablation.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Jensen Family Research Sponsorship at the University of Nebraska Medical Center

Ethmoidal and maxillary nerve block versus systemic opioid administration during rhinoscopy in dogs: a non-randomised clinical trial

OBJECTIVES

This study aimed to evaluate the clinical effects of ethmoidal and maxillary nerve blocks during rhinoscopy in dogs.

MATERIALS AND METHODS

Fourteen dogs underwent rhinoscopy. Under general anaesthesia with isoflurane, ethmoidal and maxillary nerve blocks were applied bilaterally using 2% lidocaine before rhinoscopy in eight dogs (EM group). Six dogs were premedicated with hydromorphone (0.05 mg/kg) as a substitute for local nerve block (H group). During rhinoscopy, the heart rate, arterial blood pressure and end-tidal isoflurane concentration were recorded. The vaporizer setting was adjusted to increase the end-tidal isoflurane concentration when reflex movement was caused by nasal stimulation.

RESULTS

The H group, compared to the EM group, had an increase in HR that was 18 beats/minute (95% CI: 11 to 26) higher, an increase in SAP that was 22 mmHg (12 to 31) higher, an increase in MAP that was 15 mmHg (7 to 23) higher, an increase in DAP that was 12 mmHg (5 to 19) higher, and an increase in end-tidal isoflurane concentration that was 0.4% (0.3 to 0.5) higher. Head movement due to endoscope insertion was observed in 5/6 dogs (83.3%) in the H group and 1/8 dogs (12.5%) in the EM group (odds ratio, 0.029; ra95% CI, 0.001-0.574).

CLINICAL SIGNIFICANCE

Compared with administration of 0.05 mg/kg hydromorphone, concurrent block of the ethmoidal and maxillary nerves can reduce the cardiovascular response, reflex movement and anaesthetic requirement during rhinoscopy in dogs.

AB0922 Psoriatic Arthritis Disease Activity Differs by Race/Ethnicity

Background

Psoriatic arthritis (PsA) affects up to 30% of individuals with psoriasis. Studies have demonstrated that the presenting disease severity and quality of life impact of psoriasis differs by race/ethnicity in patients with and without PsA, but little is known about disease activity among different racial/ethnic groups [1-3].

Objectives

The objective of our study was to evaluate disease activity by race/ethnicity among patients with PsA.

Methods

We performed a cross-sectional study of adult (≥18 years old) patients with PsA who had at least one outpatient visit within the University of Pennsylvania health system between 2010 and 2019. Patients with PsA were identified by the presence of at least two International Classification of Diseases (ICD)-9 or ICD-10 codes for PsA associated with two different healthcare encounters. The primary outcome was disease activity as measured by the Routine Assessment of Patient Index Data 3 (RAPID3) assessment. The RAPID3 score is a validated patient-reported measure of physical function, pain, and global status [4]. RAPID3 scores range from 0 to 30, with higher scores indicating greater disease activity. Patients were included if they had at least one documented RAPID3 score. For patients with multiple RAPID3 scores, the median value was used. The primary independent variable was race/ethnicity categorized as White (reference), Black, Asian, Hispanic, or other race. Multivariable linear regression was used to assess the relationship between race/ethnicity and RAPID 3 score.

Results

The study population included 742 patients. Mean (standard deviation [SD]) age was 47.2 (13.3) years and 57.4% were female. The racial/ethnic distribution was 79.4% White, 7.0% Black, 5.0% Asian, 3.1% Hispanic, 2.6% other race, and 3.0% missing race/ethnicity. The means of the median Rapid3 scores were statistically significantly different across racial/ethnic groups (p<.001): White mean (SD) 9.79 (6.02), Black mean (SD) 14.86 (14.86), Asian mean (SD) 9.79 (5.44), Hispanic mean (SD) 15.09 (7.11), other race mean (SD) 10.57 (6.91). In an adjusted multivariable model controlling for other sociodemographic factors, body mass index, treatment history, and medical comorbidity, Hispanic patients had higher RAPID3 scores compared to White patients, indicating greater disease activity (β 3.36; 95% confidence interval [CI] 1.04 – 5.67, p <.005). In exploratory stratified analyses to evaluate effect modification by sex, among males, Black (β 3.43; 95% CI 0.23 – 6.63, p=.04) and Hispanic (β 5.94; 95% CI 2.18 – 9.70, p <.005) patients had higher RAPID3 scores than White patients. Among females, no significant racial/ethnic differences in RAPID3 scores were identified.

Conclusion

Black and Hispanic patients report greater disease activity as indicated by higher RAPID3 scores compared to White patients. Larger studies are necessary to confirm our findings and understand the causes of racial/ethnic differences in disease activity among patients with PsA.

References

[1]Abrouk M, Lee K, Brodsky M, Nakamura M, Singh R, Zhu TH, et al. Ethnicity affects the presenting severity of psoriasis. J Am Acad Dermatol. 2017;77(1):180-2.

[2]Shah SK, Arthur A, Yang YC, Stevens S, Alexis AF. A retrospective study to investigate racial and ethnic variations in the treatment of psoriasis with etanercept. J Drugs Dermatol. 2011;10(8):866-72.

[3]Takeshita J, Augustin M, de Jong E, Lafferty K, Langholff W, Langley R, Leonardi C, Menter A, Alexis A. Psoriasis-Related Quality-of-Life Differs by Race/Ethnicity. J Invest Dermatol. 2019; 139(5S, Supplement 1):S148.

[4]Coates LC, Tillett W, Shaddick G, Pincus T, Kavanaugh A, Helliwell PS. Value of the Routine Assessment of Patient Index Data 3 in Patients With Psoriatic Arthritis: Results From a Tight-Control Clinical Trial and an Observational Cohort. Arthritis Care Res (Hoboken). 2018;70(8):1198-1205.

Disclosure of Interests

Fahad Ahmed: None declared, Alexis Ogdie Consultant of: A. Ogdie has received consulting fees from Amgen, AbbVie, Bristol Myers Squibb, Celgene, CorEvitas (formerly Corrona), Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB., Grant/research support from: A. Ogdie has received grant support from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatology Research Foundation, National Psoriasis Foundation, Abbvie (University of Pennsylvania), Pfizer (University of Pennsylvania), Amgen (FORWARD), and Novartis (FORWARD)., Robert Fitzsimmons: None declared, Daniel Shin: None declared, Junko Takeshita Consultant of: JT has served as a consultant for Pfizer Inc. and Janssen Biotech receiving honoraria., Grant/research support from: JT has received a research grant (to the Trustees of the University of Pennsylvania) from Pfizer Inc.

POS1049 ASSESSING TREATMENT PATTERNS WITH DISEASE-MODIFYING ANTIRHEUMATIC DRUGS AND PREDNISONE FOR PSORIATIC ARTHRITIS BY RACE/ETHNICITY

Background

Psoriatic arthritis (PsA) is a comorbidity commonly associated with psoriasis. Studies have demonstrated delays in the diagnosis and treatment of PsA[1] that may disproportionately affect racial/ethnic minority patients as indicated by one study that found Black Medicaid patients with PsA to be less likely to receive disease-modifying antirheumatic drugs [DMARDs] than White Medicaid patients with PsA [2]. Yet much remains unknown about potential racial/ethnic disparities in PsA management.

Objectives

The objective of our study was to evaluate treatment patterns for PsA by race/ethnicity.

Methods

We performed a cross-sectional study of adult (≥18 years old) patients with PsA who had at least one outpatient visit within the University of Pennsylvania health system between 2010 and 2019. Patients with PsA were identified by the presence of at least two International Classification of Diseases (ICD)-9 or ICD-10 codes for PsA associated with two different healthcare encounters. The primary outcomes were receipt of a prescription for: (i) an oral DMARD, (ii) a biologic DMARD, and (iii) prednisone. Oral DMARDs included apremilast, methotrexate, sulfasalazine, leflunomide, azathioprine, cyclosporine, tofacitinib, hydroxychloroquine, and upadacitnib. Biologic DMARDs included abatacept, adalimumab, brodalumab, certolizumab, etanercept, golimumab, guselkumab, infliximab, ixekixumab, secukinumab, ustekinumab, and risankizumab. The primary independent variable was race/ethnicity categorized as White (reference), Black, Asian, Hispanic, or other race. Multivariable logistic regression was used to assess the relationship between race/ethnicity and each treatment outcome.

Results

The study population included 1781 patients with PsA who were a mean age of 50.7 (SD 14.3), 54.6% female, and 72.5% commercially insured. The racial/ethnic distribution was 81.9% White, 5.6% Black, 4.0% Asian, 3.0% Hispanic, 2.5% other race, and 3.1% missing race/ethnicity. Of these patients, 64.3% were prescribed an oral DMARD, 55.6% were prescribed a biologic, and 44.1% were prescribed prednisone. There were no statistically significant differences across race/ethnicity for prescription of either oral or biologic DMARDs. However, prescription of prednisone did differ by race/ethnicity (p<.005) with Black (54.6%) and Hispanic (56.6%) patients being more likely to receive prednisone prescriptions and Asian (32.4%) patients being less likely to receive prednisone prescriptions than White (44.2%) patients. In adjusted logistic regression models controlling for sociodemographic and other factors, Hispanic patients were more likely to receive a prednisone prescription (OR 1.79, 95% CI 1.01 – 3.20, p=0.05) while Asian (OR 0.58, 95% CI 0.34 – 0.97, p=0.04) patients were less likely to receive a prednisone prescription compared to White patients.

Conclusion

We found Hispanic patients with PsA to be more likely to receive prednisone prescriptions than White patients with PsA but did not identify any racial/ethnic differences in prescription patterns for oral or biologic DMARDs for PsA. Greater use of prednisone among Hispanic patients may reflect different diseases trajectories (e.g., more disease flares or greater disease severity) or other factors that affect prescription patterns that require further study.

References

[1]Favier G, Gladman DD, Merola JF, Armstrong AW, Boehncke WH, Helliwell PS. Benchmarking Care in Psoriatic Arthritis - The QUANTUM Report: A Report from the GRAPPA 2016 Annual Meeting. J Rheumatol. 2017;44(5):674-678.

[2]Ogdie A, Matthias W, Thielen RJ, Chin D, Saffore CD. Racial Differences in Prevalence and Treatment for Psoriatic Arthritis and Ankylosing Spondylitis by Insurance Coverage in the USA. Rheumatol Ther. 2021;8(4):1725-1739.

Disclosure of Interests

Fahad Ahmed: None declared, Alexis Ogdie Consultant of: A. Ogdie has received consulting fees from Amgen, AbbVie, Bristol Myers Squibb, Celgene, CorEvitas (formerly Corrona), Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB., Grant/research support from: A. Ogdie has received grant support from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatology Research Foundation, National Psoriasis Foundation, Abbvie (University of Pennsylvania), Pfizer (University of Pennsylvania), Amgen (FORWARD), and Novartis (FORWARD)., Robert Fitzsimmons: None declared, Daniel Shin: None declared, Junko Takeshita Consultant of: JT has served as a consultant for Pfizer Inc. and Janssen Biotech receiving honoraria., Grant/research support from: JT has received a research grant (to the Trustees of the University of Pennsylvania) from Pfizer Inc.

Pre-ablation interatrial conduction delay or block predicts atrial fibrillation recurrence after ablation among obese patients

Funding Acknowledgements

Type of funding sources: None.

Background

Obesity is associated with greater risk of atrial fibrillation (AF) recurrence post-ablation and higher incidence of conduction delay compared to non-obese patients. Pre-ablation P-wave duration (PWD) and morphology (PWM) indicating interatrial delay are easily assessed in the clinic and may predict AF recurrence post-ablation in these patients.

Purpose

Evaluate the predictive value of PWD and PWM on AF recurrence post-ablation in obese patients.

Methods

Pre-ablation PWD and PWM (negative P-wave in lead II or III) were analyzed on consecutive patients with BMI ≥30 kg/m2 who underwent initial AF ablation from 2012–19. The primary outcome was recurrent AF after a 3-month post-ablation blanking period. Multivariate analysis adjusted for baseline characteristics was performed.

Results

For 205 patients (61.0±9.5 years old, 39.0% female), mean BMI was 36.9±5.7 kg/m2 and 71.7% had persistent AF pre-ablation. Recurrent AF post-ablation occurred in 115 (56.1%) during a median follow up of 491 (270, 1001) days. PWD &gt;130 ms was significantly associated with higher AF recurrence (AHR of 1.62, 95%CI 1.04-2.57, p=0.03) after adjusting for age, persistent AF and left atrial volume index (LAVI). In a subgroup with LAVI &lt;42 mL/m2 (n=112), PWD &gt;130 ms and negative P-waves in lead II or III were independently associated with increased risk of recurrent AF (AHR 2.06, 95%CI 1.12-3.91; p=0.019 and AHR 1.94, 95% CI 1.00-3.56; p=0.05, respectively) (Figure 1).

Conclusion

AF recurred in &gt;50% of obese patients within 1.5 years of ablation. Pre-ablation PWD &gt;130 ms and negative P-waves in lead II or III independently predicted recurrent AF post-ablation in this cohort of obese patients. These easily assessed findings add predictive value to other risk factors.

Electronic properties of metal halide perovskites and their interfaces: the basics

We have witnessed tremendous progress of metal halide perovskite (MHP)-based optoelectronic devices, especially in the field of photovoltaics. Despite intensive research in the past few years, questions still remain regarding their fundamental optoelectronic properties, among which the electronic properties exhibit an interplay of numerous phenomena that deserve serious scrutiny. In this Focus article, we aim to provide a contemporary understanding of the unique electronic properties that has been resolved by the community. First introducing some of the basic concepts established in semiconductor physics, the intrinsic and extrinsic electronic properties of the MHPs are disentangled and explained. With this, the complex interplay of interface-, dopant-, and surface state-induced electronic states in determining the electrostatic landscape in the material can be comprehended, and the energy level alignment in device architectures more reliably assessed.

Photoinduced Energy-Level Realignment at Interfaces between Organic Semiconductors and Metal-Halide Perovskites

In contrast to the common conception that the interfacial energy-level alignment is affixed once the interface is formed, we demonstrate that heterojunctions between organic semiconductors and metal-halide perovskites exhibit huge energy-level realignment during photoexcitation. Importantly, the photoinduced level shifts occur in the organic component, including the first molecular layer in direct contact with the perovskite. This is caused by charge-carrier accumulation within the organic semiconductor under illumination and the weak electronic coupling between the junction components.

Changing demographics, temporal trend in waitlist and post-transplant outcomes after heart transplantation in the United States: analysis of unos database 1991–2019

Background

The landscape of heart transplantation (HT) has changed significantly with respect to patient selection, surgical techniques, and patient outcomes. We sought to investigate temporal trends in patient characteristics, waitlist and post-transplant outcomes after HT in the U.S.

Methods

We queried the national database of the United Network of Organ Sharing (UNOS) to identify adults listed for HT in the U.S. between 1991 and 2019. Patients were divided into four eras based on the three time points in which changes were made to the patient selection/allocation policy (1999, 2006, and 2018), and patient characteristics as well as waitlist and post-transplant outcomes were evaluated for each era.

Results

Between 1991 and 2019, a total of 95,179 patients were added to the waitlist for HT in the U.S. Compared to era 1, patients listed in era 4 were older (mean age: 52.4 years), more female (27.6%) and ethnic minorities (40%), and with higher-risk comorbidities (28.8% diabetes, 35.6% obese). Over the study period, there were 22,070 waitlist deaths and 61,687 transplants.

Compared to the preceding era, there was significant decrease in waitlist mortality in the last 2 eras (e.g., sub-hazard ratio for era 4 vs era 3 =0.37, 95% CI=0.32–0.44). For each year, only 27.1% to 40.5% of those on the waitlist were transplanted. Among those who were transplanted, there was increase in the rates of in-hospital stroke (2.8% in era 1 to 3.7% in era 4), renal failure requiring dialysis (7.2% to 17.1%), and hospital length of stay (14 to 17 days), p-values&lt;0.001 for all. However, this has not negatively impacted short-term survival when compared to the preceding era (1-year graft survival = 89.7% in era 4). Based on a projection model, we predict a 47% increase in living adult heart transplant recipients to to 44,366 in 2040.

Conclusion

There have been significant changes in the characteristics of patients listed for HT in the U.S., including an increasing proportion of high-risk co-morbidities. Although the transplant volume has increased, the wide supply-demand gap persisted. The last 2 changes in the allocation policy in 2006 and 2018 achieved their primary objective of reducing waitlist mortality.

Funding Acknowledgement

Type of funding sources: None.

The Schottky-Mott Rule Expanded for Two-Dimensional Semiconductors: Influence of Substrate Dielectric Screening

A comprehensive understanding of the energy level alignment mechanisms between two-dimensional (2D) semiconductors and electrodes is currently lacking, but it is a prerequisite for tailoring the interface electronic properties to the requirements of device applications. Here, we use angle-resolved direct and inverse photoelectron spectroscopy to unravel the key factors that determine the level alignment at interfaces between a monolayer of the prototypical 2D semiconductor MoS₂ and conductor, semiconductor, and insulator substrates. For substrate work function (Φ_sub) values below 4.5 eV we find that Fermi level pinning occurs, involving electron transfer to native MoS₂ gap states below the conduction band. For Φ_sub above 4.5 eV, vacuum level alignment prevails but the charge injection barriers do not strictly follow the changes of Φ_sub as expected from the Schottky-Mott rule. Notably, even the trends of the injection barriers for holes and electrons are different. This is caused by the band gap renormalization of monolayer MoS₂ by dielectric screening, which depends on the dielectric constant (ε_r) of the substrate. Based on these observations, we introduce an expanded Schottky-Mott rule that accounts for band gap renormalization by ε_r -dependent screening and show that it can accurately predict charge injection barriers for monolayer MoS₂. It is proposed that the formalism of the expanded Schottky-Mott rule should be universally applicable for 2D semiconductors, provided that material-specific experimental benchmark data are available.

Temperature-Dependent Electronic Ground-State Charge Transfer in van der Waals Heterostructures

Electronic charge rearrangement between components of a heterostructure is the fundamental principle to reach the electronic ground state. It is acknowledged that the density of state distribution of the components governs the amount of charge transfer, but a notable dependence on temperature is not yet considered, particularly for weakly interacting systems. Here, it is experimentally observed that the amount of ground-state charge transfer in a van der Waals heterostructure formed by monolayer MoS₂ sandwiched between graphite and a molecular electron acceptor layer increases by a factor of 3 when going from 7 K to room temperature. State-of-the-art electronic structure calculations of the full heterostructure that accounts for nuclear thermal fluctuations reveal intracomponent electron-phonon coupling and intercomponent electronic coupling as the key factors determining the amount of charge transfer. This conclusion is rationalized by a model applicable to multicomponent van der Waals heterostructures.

Mechanism and Timescales of Reversible p-Doping of Methylammonium Lead Triiodide by Oxygen

Understanding and controlling the energy level alignment at interfaces with metal halide perovskites (MHPs) is essential for realizing the full potential of these materials for use in optoelectronic devices. To date, however, the basic electronic properties of MHPs are still under debate. Particularly, reported Fermi level positions in the energy gap vary from indicating strong n- to strong p-type character for nominally identical materials, raising serious questions about intrinsic and extrinsic defects as dopants. ​In this work, photoemission experiments demonstrate that thin films of the prototypical methylammonium lead triiodide (MAPbI₃ ) behave like an intrinsic semiconductor in the absence of oxygen. Oxygen is then shown to be able to reversibly diffuse into and out of the MAPbI₃ bulk, requiring rather long saturation timescales of ≈1 h (in: ambient air) and over 10 h (out: ultrahigh vacuum), for few 100 nm thick films. Oxygen in the bulk leads to pronounced p-doping, positioning the Fermi level universally ≈0.55 eV above the valence band maximum. The key doping mechanism is suggested to be molecular oxygen substitution of iodine vacancies, supported by density functional theory calculations. This insight rationalizes previous and future electronic property studies of MHPs and calls for meticulous oxygen exposure protocols.

Type-I Energy Level Alignment at the PTCDA-Monolayer MoS2 Interface Promotes Resonance Energy Transfer and Luminescence Enhancement

Van der Waals heterostructures consisting of 2D semiconductors and conjugated molecules are of increasing interest because of the prospect of a synergistic enhancement of (opto)electronic properties. In particular, perylenetetracarboxylic dianhydride (PTCDA) on monolayer (ML)-MoS2 has been identified as promising candidate and a staggered type-II energy level alignment and excited state interfacial charge transfer have been proposed. In contrast, it is here found with inverse and direct angle resolved photoelectron spectroscopy that PTCDA/ML-MoS2 supported by insulating sapphire exhibits a straddling type-I level alignment, with PTCDA having the wider energy gap. Photoluminescence (PL) and sub-picosecond transient absorption measurements reveal that resonance energy transfer, i.e., electron-hole pair (exciton) transfer, from PTCDA to ML-MoS2 occurs on a sub-picosecond time scale. This gives rise to an enhanced PL yield from ML-MoS2 in the heterostructure and an according overall modulation of the photoresponse. These results underpin the importance of a precise knowledge of the interfacial electronic structure in order to understand excited state dynamics and to devise reliable design strategies for optimized optoelectronic functionality in van der Waals heterostructures.

Residual functional SYNTAX score by quantitative flow ratio and improvement of exercise capacity after revascularization in patients with stable ischemic heart disease

Background

In patients with stable ischemic heart disease (SIHD), the efficacy of percutaneous coronary intervention (PCI) in improving exercise capacity has been under debate and the differential effect of PCI for exercise capacity, according to functional completeness of revascularization, has not been evaluated.

Purpose

This study aimed to evaluate the association between improvement in exercise capacity and functional completeness of revascularization, determined by residual functional SYNTAX score (rFSS), which is the sum of residual SYNTAX score of the vessels with post-PCI quantitative flow ratio (QFR)≤0.80.

Methods

Among patients enrolled in the QFR multicenter registry, 110 patients who underwent prespecified routine exercise treadmill tests before and after PCI were analyzed. Patients were classified into functional complete revascularization (CR) group (rFSS=0) and functional incomplete revascularization (IR) group (rFSS≥1). Increase of exercise time after PCI was compared between the 2 groups. Improvement of exercise capacity was defined as ≥10% increase of exercise time after PCI.

Results

Functional CR was achieved in 79 patients (71.8%), otherwise classified as functional IR in 31 patients (18.2%). There were no significant differences in baseline characteristics including medication profiles. Increase of exercise time was significantly associated with increase of 3-vessel QFR (r=0.198, P=0.038) and rFSS (r=−0.312, P&lt;0.001), but not with decrease of SYNTAX score (r=0.097, P=0.313). The rFSS showed significantly higher c-index to predict the improvement of exercise capacity after PCI than increase of 3-vessel QFR or decrease of SYNTAX score (0.722 vs. 0.627 vs. 0.492, respectively, P&lt;0.001). Patients with functional CR, defined by rFSS, showed significantly higher increase of exercise time than those with functional IR (97.7 sec vs. 12.5 sec, P&lt;0.001). Functional CR was an independent predictor of the improvement of exercise capacity after PCI (adjusted odds ratio 4.656, 95% CI 1.678–12.920, P=0.002).

Conclusions

Integrated anatomic and functional scoring system (rFSS) was significantly associated with improvement of exercise capacity after PCI. SIHD patients with functional CR, defined by rFSS, showed significantly higher exercise capacity after PCI than those with functional IR.

Summarizing Figure

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): SaeHan NK & D and Medis Corporation

Position-locking of volatile reaction products by atmosphere and capping layers slows down photodecomposition of methylammonium lead triiodide perovskite

The remarkable progress of metal halide perovskites in photovoltaics has led to the power conversion efficiency approaching 26%. However, practical applications of perovskite-based solar cells are challenged by the stability issues, of which the most critical one is photo-induced degradation. Bare CH₃NH₃PbI₃ perovskite films are known to decompose rapidly, with methylammonium and iodine as volatile species and residual solid PbI₂ and metallic Pb, under vacuum under white light illumination, on the timescale of minutes. We find, in agreement with previous work, that the degradation is non-uniform and proceeds predominantly from the surface, and that illumination under N₂ and ambient air (relative humidity 20%) does not induce substantial degradation even after several hours. Yet, in all cases the release of iodine from the perovskite surface is directly identified by X-ray photoelectron spectroscopy. This goes in hand with a loss of organic cations and the formation of metallic Pb. When CH₃NH₃PbI₃ films are covered with a few nm thick organic capping layer, either charge selective or non-selective, the rapid photodecomposition process under ultrahigh vacuum is reduced by more than one order of magnitude, and becomes similar in timescale to that under N₂ or air. We conclude that the light-induced decomposition reaction of CH₃NH₃PbI₃, leading to volatile methylammonium and iodine, is largely reversible as long as these products are restrained from leaving the surface. This is readily achieved by ambient atmospheric pressure, as well as a thin organic capping layer even under ultrahigh vacuum. In addition to explaining the impact of gas pressure on the stability of this perovskite, our results indicate that covalently “locking” the position of perovskite components at the surface or an interface should enhance the overall photostability.

Gas pressure and capping layers under ultrahigh vacuum prevent methylammonium lead triiodide photo-degradation due to efficient back-reaction of volatile compounds.

Band Alignment Engineering between Planar SnO2 and Halide Perovskites via Two-Step Annealing

Managing defects in SnO₂ is critical for improving the power conversion efficiency (PCE) of halide perovskite-based solar cells. However, typically reported SnO_2-based perovskite solar cells have inherent defects in the SnO₂ layer, which lead to a lower PCE and hysteresis. Here, we report that a dual-coating approach for SnO₂ with different annealing temperatures can simultaneously form a SnO₂ layer with high crystallinity and uniform surface coverage. Along with these enhanced physical properties, the dual-coated SnO₂ layer shows favorable band alignment with a mixed halide perovskite. After careful optimization of the dual-coating method, the average PCE of the perovskite solar cell based on the dual-coated SnO₂ layer increases from 18.07 to 19.23% with a best-performing cell of 20.03%. Note that a facile two-step coating and annealing method can open new avenues to develop SnO₂-based perovskite solar cells with stabilized and improved photovoltaic performances.

Massive clonal expansion of medulloblastoma-specific T cells during adoptive cellular therapy

In both human and murine systems, we have developed an adoptive cellular therapy platform against medulloblastoma and glioblastoma that uses dendritic cells pulsed with a tumor RNA transcriptome to expand polyclonal tumor-reactive T cells against a plurality of antigens within heterogeneous brain tumors. We demonstrate that peripheral TCR Vβ repertoire analysis after adoptive cellular therapy reveals that effective response to adoptive cellular therapy is concordant with massive in vivo expansion and persistence of tumor-specific T cell clones within the peripheral blood. In preclinical models of medulloblastoma and glioblastoma, and in a patient with relapsed medulloblastoma receiving adoptive cellular therapy, an early and massive expansion of tumor-reactive lymphocytes, coupled with prolonged persistence in the peripheral blood, is observed during effective therapeutic response to immunotherapy treatment.

Electronic Structure of Nonionic Surfactant-Modified PEDOT:PSS and Its Application in Perovskite Solar Cells with Reduced Interface Recombination

The interfacial properties of organolead halide perovskite solar cells (PSCs) affect the exciton and charge-transport dynamics significantly. Thus, proper modification of the interfaces between perovskite and charge-transport layers is an efficient method to increase the power conversion efficiency (PCE) of PSCs. In this work, we explore the effect of a nonionic surfactant, that is, Triton X-100 (TX) additive, in the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) hole-transport layer. The electronic structure of TX-modified PEDOT:PSS is investigated with ultraviolet/X-ray photoelectron spectroscopy and X-ray absorption spectroscopy with various TX concentrations. The surface of the TX-modified PEDOT:PSS layer showed high TX content, and thus the semimetallic properties of PEDOT:PSS were suppressed conspicuously by its insulating nature. With the TX-modified PEDOT:PSS, the PCE of methylammonium lead iodide (MAPbI₃) PSCs increased significantly. To elucidate the origin of the improved device performance, the electrical properties and photoluminescence were investigated comprehensively. Consequently, it was found that the TX additive inhibits interface recombination between PEDOT:PSS and MAPbI₃, which is caused by the suppression of semimetallic properties of the PEDOT:PSS surface. Hence, we fabricated flexible PSCs successfully using a graphene electrode and TX-modified PEDOT:PSS.