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Funding Information: This project was primarily supported by the National Key R&D Program of China (Grant 2018YFA0307200), the National Natural Science Foundation of China (Grants 91950119, 61905196, and 62090033), Key Research and Development Program in Shaanxi Province of China (Grant 2020JZ-10), and the Fundamental Research Funds for the Central Universities (Grants 310201911cx032, 3102019JC008, and D5000210905). The authors also thank the Analytical & Testing Center of NPU for their assistance in device fabrication and characterizations. Publisher Copyright: © 2022 American Chemical Society. Two-dimensional (2D) materials, featuring distinctive electronic and optical properties and dangling-bond-free surfaces, are promising for developing high-performance on-chip photodetectors in photonic integrated circuits. However, most of the previously reported devices operating in the photoconductive mode suffer from a high dark current or a low responsivity. Here, we demonstrate a MoTe2p-i-n homojunction fabricated directly on a silicon photonic crystal (PC) waveguide, which enables on-chip photodetection with ultralow dark current, high responsivity, and fast response speed. The adopted silicon PC waveguide is electrically split into two individual back gates to selectively dope the top regions of the MoTe2 channel in p- or n-types. High-quality reconfigurable MoTe2 (p-i-n, n-i-p, n-i-n, p-i-p) homojunctions are realized successfully, presenting rectification behaviors with ideality factors approaching 1.0 and ultralow dark currents less than 90 pA. Waveguide-assisted MoTe2 absorption promises a sensitive photodetection in the telecommunication O-band from 1260 to 1340 nm, though it is close to MoTe2's absorption band-edge. A competitive photoresponsivity of 0.4 A/W is realized with a light on/off current ratio exceeding 104 and a record-high normalized photocurrent-to-dark-current ratio of 106 mW-1. The ultrasmall capacitance of p-i-n homojunction and high carrier mobility of MoTe2 promise a high dynamic response bandwidth close to 34.0 GHz. The proposed device geometry has the advantages of employing a silicon PC waveguide as the back gates to build a 2D material p-i-n homojunction directly and simultaneously to enhance light-2D material interaction. It provides a potential pathway to develop 2D material-based photodetectors, laser diodes, and electro-optic modulators on silicon photonic chips.

Two-dimensional (2D) materials, featuring distinctive electronic and optical properties and dangling-bond-free surfaces, are promising for developing high-performance on-chip photodetectors in photonic integrated circuits. However, most of the previously reported devices operating in the photoconductive mode suffer from a high dark current or a low responsivity. Here, we demonstrate a MoTe

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A compact electrical source capable of generating surface plasmon polaritons would represent a crucial step for on-chip plasmonic circuitry. The device fabrication of plasmonic actuator based on Au/SiO2/n++Si tunnel junction and performance have been reported in [ACS photonics, 2021, 8, 7, 1951–1960]. This work focuses on the underlying mechanisms of electroluminescence. The n-type Si samples were doped with concentrations ranging from 1.6 × 1015 cm−3 to 1.0 × 1020 cm−3. A low voltage of 1.4 V for intense light emission was achieved at the highest concentration. The electrical/spectral characteristics and energy band diagrams calculation show two distinct behaviors indicating two distinct mechanisms of light emission are at work in the heavily doped versus the lightly doped Si. In the heavily doped case, the light output is correlated to tunneling current and the subsequent conversion of surface plasmons to photons, while that for the lightly doped case is due to indirect band-to-band recombination in silicon. The results are validated by numerical simulation which indicates that the heavy doping of the n++-Si is necessary to achieve surface plasmon generation via electron tunneling due to the presence of band tail states and their effect on lowering the barrier height.

Light emission from metal-insulator-semiconductor junctions (MISJs) has been explored for decades as a possible on-chip light source; however it is not clear whether the mechanism of light emission is plasmonic in nature or is dominated by electroluminescence. Previous studies only investigated silicon with low doping levels, but here we show that only highly doped silicon allows us to excite surface plasmon polaritons (SPPs) in MISJs via inelastic tunneling. This paper describes the mechanism of charge transport and light emission from silicon-based Au-SiO2-nSi MISJs as a function of the doping level Nd varying from 1.6 × 1015 cm-3 to 1.0 × 1020 cm-3. At low doping levels (Nd ∼1015 cm-3), the MISJs behave as Schottky diodes, and the mechanism of light emission involves a radiative recombination of electrons and holes from minority carrier injection under high applied bias (>5.5 V). With increasing doping levels, the current-voltage characteristics of the MISJs change, resulting in symmetrical current-voltage curves with parabolic conductance behavior characteristic of quantum mechanical tunneling. MISJs with the highest doping level (Nd ∼1020 cm-3) are dominated by quantum mechanical tunneling, and light emission originates from radiative decay of surface plasmon polaritons (SPPs) via scattering at threshold voltages as low as 1.5 V. Our simulations indicate that tunneling over the thin SiO2 barrier between the Au and highly doped nSi excites a hybrid-SPP mode localized to the Au whose dispersion depends on the effective index induced by the SiO2-nSi interface. Our studies show that Si needs to be sufficiently doped to be conductive enough to enable SPP excitation via inelastic tunneling.

Background: Cardiac evaluation before deceased donor kidney transplant (DDKT) remains a matter of debate. Data on Asian countries and countries with prolonged waiting times are lacking. This study aimed to assess the outcomes of patients referred for DDKT after a cardiac evaluation at an Asian tertiary transplant center. Methods: This single-center retrospective review analyzed patients who were referred for waitlist placement and underwent cardiac stress testing between January 2009 and December 2015. Patients with cardiac symptoms were excluded. The primary outcome was three-point major adverse cardiovascular events (MACE), a composite of non-fatal myocardial infarction, non-fatal stroke, and cardiovascular death. Results: Of 468 patients referred for DDKT, 198 who underwent cardiac stress testing (myocardial perfusion studies in 159 patients and stress echocardiography in 39 patients) were analyzed. MACE occurred in 20.7% of the patients over a median follow-up of 4.6 years. Cardiac stress tests were positive for ischemia in 19.7% of the patients. Coronary angiography was performed in 63 patients, including 29 patients with diabetic kidney disease and negative cardiac stress tests. Significant coronary artery disease (CAD) was detected in 27 patients (42.8%), of whom 18 underwent revascularization. MACE was associated with significant CAD on coronary angiography in the multivariable analysis. Cardiac stress test results were not associated with MACE. Amongst diabetic patients who had negative cardiac stress tests, 37.9% had significant CAD on coronary angiography. Conclusions: The cardiovascular disease burden is significant amongst DDKT waitlist candidates. Pretransplant cardiac screening may identify patients with significant CAD at higher risk of MACE. Published version

Introduction: Perceived benefits like decreased contamination rates and reduced postoperative incidence of complications after urolithiasis surgery have led to increased adoption of single-use flexible ureteroscopes (su-fURS). Using a validated, standardized simulator model with enhanced “fluoroscopic” capabilities, we performed an in vitro comparative assessment of four commercially available models of su-fURS. Both objective and subjective parameters were assessed in this study. Methods: Two standardized tasks, (1) exploration of the model’s kidney collecting system and (2) repositioning of a stone fragment from the upper renal to lower renal pole were assigned to participants, who performed these tasks on all four scopes. Four models of su-fURS (Boston LithoVue, PUSEN PU3033A, REDPINE, INNOVEX EU-ScopeTM) were assessed, with task timings as end-points for objective analysis. Cumulative “fluoroscopic” time was also recorded as a novel feature of our enhanced model. Post-task questionnaires evaluating specific components of the scopes were distributed to document subjective ratings. Results: Both subjective and objective performances (except stone repositioning time) across all four su-fURS demonstrated significant differences. However, objective performance (task timings) did not reflect subjective scope ratings by the participants (Rs < 0.6). Upon Kruskal-Wallis H test with post hoc analyses, REDPINE and INNOVEX EU-ScopeTM were the preferred su-fURS as rated by the participants, with overall scope scores of 9.00/10 and 9.57/10. Conclusions: Using a standardized in vitro simulation model with enhanced fluoroscopic capabilities, we demonstrated both objective and subjective differences between models of su-fURS. However, variations in perception of scope features (visibility, image quality, deflection, maneuverability, ease of stone retrieval) did not translate into actual technical performance. Eventually, the optimal choice of su-fURS fundamentally lies in individual surgeon preference, as well as cost-related factors.

Background Coronary artery calcium score (CAC) is an objective marker of atherosclerosis. The primary aim is to assess CAC as a risk classifier in stable coronary artery disease (CAD). Hypothesis CAC improves CAD risk prediction, compared to conventional risk scoring, even in the absence of cardiovascular risk factor inputs. Methods Outpatients presenting to a cardiology clinic (n = 3518) were divided into two cohorts: derivation (n = 2344 patients) and validation (n = 1174 patients). Adding logarithmic transformation of CAC, we built two logistic regression models: Model 1 with chest pain history and risk factors and Model 2 including chest pain history only without risk factors simulating patients with undiagnosed comorbidities. The CAD I Consortium Score (CCS) was the conventional reference risk score used. The primary outcome was the presence of coronary artery disease defined as any epicardial artery stenosis≥50% on CT coronary angiogram. Results Area under curve (AUC) of CCS in our validation cohort was 0.80. The AUC of Models 1 and 2 were significantly improved at 0.88 (95%CI 0.86-0.91) and 0.87 (95%CI 0.84-0.90), respectively. Integrated discriminant improvement was >15% for both models. At a pre-specified cut-off of ≤10% for excluding coronary artery disease, the sensitivity and specificity were 89.3% and 74.7% for Model 1, and 88.1% and 71.8% for Model 2. Conclusion CAC helps improve risk classification in patients with chest pain, even in the absence of prior risk factor screening.

A CMOS-compatible plasmonic waveguide with a metal or metal-like strip sandwiched in-between dielectrics has been proposed for intra-chip communication in the more-than-Moore era. A sequence of numerical models has been presented to evaluate the plasmonic waveguide performance. For device-level consideration, we demonstrated through simulations that Cu (1450 nm pitch) and PLD-TiN (900 nm pitch) plasmonic waveguides symmetrically sandwiched by SiO₂ with much smaller and hence denser interconnects,are promising candidates for use in global wires for the asynchronous communication. This design of plasmonic waveguide can bridge the CMOS circuitry and high-speed communication at optical frequencies within chip. For a system-level assessment, both of them have the same bandwidth throughput of∼19.8 Gbps. The other performance parameters of Cu and PLD-TiN plasmonic waveguides are respectively, signal latency of ∼0.18 ps and 0.19 ps,energy dissipation per computing bit of ∼2.5×10⁻³ fJ/bit and 3.8×10⁻³ fJ/bit, and 25% crosstalk coupling length of 155μm and 125μm. These findings suggest that plasmonic waveguide for intra-chip communication surpass those of existing electronic interconnects for all the categories of performance parameters. National Research Foundation (NRF) Published version This research was supported by National Research Foundation Singapore project of Integration of Electrically Driven Plasmonic Components in High Speed (NRF2016_CRP001_111).

To develop methods to generate, manipulate, and detect plasmonic signals by electrical means with complementary metal-oxide-semiconductor (CMOS)-compatible materials is essential to realize on-chip electronic-plasmonic transduction. Here, electrically driven, CMOS-compatible electronic-plasmonic transducers with Al-AlOX -Cu tunnel junctions as the excitation source of surface plasmon polaritons (SPPs) and Si-Cu Schottky diodes as the detector of SPPs, connected via plasmonic strip waveguides of Cu, are demonstrated. Remarkably, the electronic-plasmonic transducers exhibit overall transduction efficiency of 1.85 ± 0.03%, five times higher than previously reported transducers with two tunnel junctions (metal-insulator-metal (MIM)-MIM transducers) where SPPs are detected based on optical rectification. The result establishes a new platform to convert electronic signals to plasmonic signals via electrical means, paving the way toward CMOS-compatible plasmonic components.

© 2022 Editorial Office of Asian Journal of UrologyObjective: To scrutinize the definitions of minimal invasive surgical therapy (MIST) and to investigate urologists’ knowledge, attitude, and practices for benign prostatic obstruction surgeries. Methods: A 36-item survey was developed with a Delphi method. Questions on definitions of MIST and attitude and practices of benign prostatic obstruction surgeries were included. Urologists were invited globally to complete the online survey. Consensus was achieved when more than or equal to 70% responses were \"agree or strongly agree\" and less than or equal to 15% responses were \"disagree or strongly disagree\" (consensus agree), or when more than or equal to 70% responses were \"disagree or strongly disagree\" and less than or equal to 15% responses were \"agree or strongly agree\" (consensus disagree). Results: The top three qualities for defining MIST were minimal blood loss (n=466, 80.3%), fast post-operative recovery (n=431, 74.3%), and short hospital stay (n=425, 73.3%). The top three surgeries that were regarded as MIST were Urolift® (n=361, 62.2%), Rezum® (n=351, 60.5%), and endoscopic enucleation of the prostate (EEP) (n=332, 57.2%). Consensus in the knowledge section was achieved for the superiority of Urolift®, Rezum®, and iTIND® over transurethral resection of the prostate with regards to blood loss, recovery, day surgery feasibility, and post-operative continence. Consensus in the attitudes section was achieved for the superiority of Urolift®, Rezum®, and iTIND® over transurethral resection of the prostate with regards to blood loss, recovery, and day surgery feasibility. Consensus on both sections was achieved for EEP as the option with the better symptoms and flow improvement, lower retreatment rate, and better suitable for prostate more than 80 mL. Conclusion: Minimal blood loss, fast post-operative recovery, and short hospital stay were the most important qualities for defining MIST. Urolift®, Rezum®, and EEP were regarded as MIST by most urologists.