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Graphene field-effect transistor (GFET) biosensors exhibit high sensitivity due to a large surface-to-volume ratio and the high sensitivity of the Fermi level to the presence of charged biomolecules near the surface. For most reported GFET biosensors, bulky external reference electrodes are used which prevent their full-scale chip integration and contribute to higher costs per test. In this study, GFET arrays with on-chip integrated liquid electrodes were employed for COVID-19 detection and functionalized with either antibody or aptamer to selectively bind the spike proteins of SARS-CoV-2. In the case of the aptamer-functionalized GFET (aptasensor, Apt-GFET), the limit-of-detection (LOD) achieved was about 10

Glial fibrillary acidic protein (GFAP) is a discriminative blood biomarker for many neurological diseases, such as traumatic brain injury. Detection of GFAP in buffer solutions using biosensors has been demonstrated, but accurate quantification of GFAP in patient samples has not been reported, yet in urgent need. Herein, we demonstrate a robust on-chip graphene field-effect transistor (GFET) biosensing method for sensitive and ultrafast detection of GFAP in patient plasma. Patients with moderate–severe traumatic brain injuries, defined by the Mayo classification, are recruited to provide plasma samples. The binding of target GFAP with the specific antibodies that are conjugated on a monolayer GFET device triggers the shift of its Dirac point, and this signal change is correlated with the GFAP concentration in the patient plasma. The limit of detection (LOD) values of 20 fg/mL (400 aM) in buffer solution and 231 fg/mL (4 fM) in patient plasma have been achieved using this approach. In parallel, for the first time, we compare our results to the state-of-the-art single-molecule array (Simoa) technology and the classic enzyme-linked immunosorbent assay (ELISA) for reference. The GFET biosensor shows competitive LOD to Simoa (1.18 pg/mL) and faster sample-to-result time (

BACKGROUND: Atrial fibrillation (AF) is associated with significant morbidity and is predicted by atrial high rate events. The early detection of AF is paramount to timely interventions to reduce the morbidity of AF. The DX ICD system combined with Home Monitoring® allows for continuous atrial rhythm monitoring without the need for a dedicated atrial lead. OBJECTIVE: To establish the reaction to and timing of reactions to the detection of atrial high rate episodes (AHRE). METHODS: A prospective cohort of DX ICD systems was followed up and the response to AHREs was collected and evaluated. RESULTS: A total of 234 patients were enrolled; an AHRE ⩾ 6 min was detected in 13.7% of patients (n= 32) within a mean follow-up duration of 16 months. A high rate of oral anticoagulation (OAC) prescription was seen with the detection of AHREs in patients with a not-low risk CHA2DS2-VASc score. There was a delay in this prescription highlighting the potential to improve the timeliness of patient care in this group of patients. CONCLUSIONS: The DX ICD system provides rapid and ongoing atrial rhythm monitoring such that physicians are rapidly aware of AHRE without the need for a dedicated atrial lead, but local protocols are needed to improve the response time of anti-coagulation prescription.

Treatment with the wearable cardioverter defibrillator (WCD) may protect against sudden cardiac death (SCD) as a bridging therapy until a cardioverter-defibrillator may be implanted. We analyzed in a multicenter setting a consecutive patient cohort wearing WCD to explore sex differences.We analyzed 708 consecutive patients, 579 (81.8%) from whom were males and 129 (18.2%) females (age, 60.5 ± 14 vs. 61.6 ± 17 years old; p = .44). While the rate of ischemic cardiomyopathy (ICM) as a cause of prescription of WCD was significantly higher in males as compared to females (42.7% vs. 26.4%; p = .001), females received it more frequently due to nonischemic cardiomyopathy (NICM) (55.8% vs. 42.7%); p = .009). The wear time of WCD was equivalent in both groups (21.1 ± 4.3 h/days in males vs. 21.5 ± 4.4 h/days in females; p = .27; and 62.6 ± 44.3 days in males vs. 56.5 ± 39 days in females; p = .15). Mortality was comparable in both groups at 2-year-follow-up (6.8% in males vs. 9.7% in females; p = .55). Appropriate WCD shocks and the incidence of ICD implantations were similar in both groups (2.4% in males vs. 3.9% in females; p = .07) (35.1% in males vs. 31.8% in females; p = .37), respectively. In age tertile analysis, compliance was observed more in 73-91 years old group as compared with 14-51 years old group (87.8% vs. 68.3%; p .001).Compliance for wearing WCD was excellent regardless of sex. Furthermore, mortality and the incidence of ICD implantations were comparable in both sexes. Appropriate WCD shocks were similar in both sexes.

Graphene field-effect transistors (GFETs) are suitable building blocks for high-performance electrical biosensors, because graphene inherently exhibits a strong response to charged biomolecules on its surface. However, achieving ultralow limit-of-detection (LoD) is limited by sensor response time and screening effect. Herein, we demonstrate that the detection limit of GFET biosensors can be improved significantly by decorating the uncovered graphene sensor area with carbon dots (CDs). The developed CDs-GFET biosensors used for exosome detection exhibited higher sensitivity, faster response, and three orders of magnitude improvements in the LoD compared with nondecorated GFET biosensors. A LoD down to 100 particles/μL was achieved with CDs-GFET sensor for exosome detection with the capability for further improvements. The results were further supported by atomic force microscopy (AFM) and fluorescent microscopy measurements. The high-performance CDs-GFET biosensors will aid the development of an ultrahigh sensitivity biosensing platform based on graphene for rapid and early diagnosis of diseases.

The performance of graphene devices is often limited by defects and impurities induced during device fabrication. Polymer residue left on the surface of graphene after photoresist processing can increase electron scattering and hinder electron transport. Furthermore, exposing graphene to plasma-based processing such as sputtering of metallization layers can increase the defect density in graphene and alter the device performance. Therefore, the preservation of the high-quality surface of graphene during thin-film deposition and device manufacturing is essential for many electronic applications. Here, we show that the use of self-assembled monolayers (SAMs) of hexamethyldisilazane (HMDS) as a buffer layer during the device fabrication of graphene can significantly reduce damage, improve the quality of graphene, and enhance device performance. The role of HMDS has been systematically investigated using surface analysis techniques and electrical measurements. The benefits of HMDS treatment include a significant reduction in defect density compared with as-treated graphene and more than a 2-fold reduction of contact resistance. This surface treatment is simple and offers a practical route for improving graphene device interfaces, which is important for the integration of graphene into functional devices such as electronics and sensor devices.

Dielectric measurements offer the possibility of highly sensitive detection of physical cell properties, and are of interest for clinical applications due to their non-destructive nature and the lack of need for cell labelling. Here we report sensitive measurements on single, living, free-flowing cells (not electrostatically or dielectrophoretically trapped, cultured or fixed directly on sensing elements) in aqueous medium at ∼9.8 GHz taken using a coupled dielectric-split ring resonator assembly. Inductive coupling between the two resonators enabled separation of microfluidic chips from RF connectors and allowed for time-resolved continuous-wave measurements on flowing single cells via the coaxial ports of a dielectric-loaded microwave cavity. Analysis via an equivalent circuit model showed that the novel resonator assembly maintained the permittivity-dependent sensitivity of a split ring resonator while operating at quality factors >1000 with lossy aqueous media (typically ∼1900). Using a microfluidic channel with a 300 × 300 μm cross section, at a water-loaded resonant amplitude of ∼−22 dB at 0 dBm input power level, shifts in amplitude due to individual cells passing through the sensing region of up to −0.0015 dB were observed. Correlations between averaged amplitude shifts and cell size as well as material properties demonstrate the diagnostic potential of this technique.

The solid electrolyte interphase (SEI) is critical for lithium-ion batteries (LIBs). Understanding and control over how the SEI is formed is therefore essential to develop LIBs with improved coulombic efficiency, lifetime and capacity. Previous research has focused on how variations in electrolyte chemistry and charging conditions can manipulate the SEI, yet there remains a fundamental lack of understanding surrounding the formation mechanism of the SEI. Specifically, there is minimal research on how the electrode material itself influences the formation of the SEI. Herein, chemically equivalent yet electronically distinct mono-, bi- and multi-layered graphene are used as LIB anodes. The formation of the SEI is probed with respect to kinetics, mechanism, morphology, and composition. SEI films on monolayer graphene contain high amounts of decomposition products from the salt (LiPF6) while on multilayer graphene, the films contain a large proportion of organic products. The basal plane of SEI films contains more organic species in the side close to the electrode than close to the electrolyte because of the intrinsic charge transfer between the solvents and graphitic anodes. We demonstrate that the composition of SEI films is tunable by modifying the reduction capability of the anode relative to the electrolyte where high reduction kinetics promotes LiPF6 decomposition; low reduction kinetics leads to more solvent decomposition and sluggish phase change during SEI deposition. This work provides fundamental insights into the influence of electrode electronic structure on SEI formation, and provides future directions to improve LIBs.

Aims The treatment with the wearable cardioverter defibrillator (WCD) may protect against sudden cardiac death (SCD) as a bridging therapy until a cardioverter-defibrillator may be implanted. We analyzed in a multicenter setting a consecutive patient cohort wearing WCD to explore gender differences. Methods and results We analyzed 708 consecutive patients, 579 from whom were males and 129 females (age, 60.5±14 vs. 61.6±17 years old; p=0.44). All patients were divided into age quartiles for analysis. While the rate of ischemic cardiomyopathy (ICM) as a cause of prescription of WCD was significantly higher in males as compared to females (42.7% vs. 26.4%; p=0.001), females received it more frequently due to non-ischemic cardiomyopathy (NICM) (55.8% vs. 42.7%); p=0.009). The wear time of WCD was equivalent in both groups (21.1±4.3 hours/days in males vs. 21.5±4.4 hours/days in females; p=0.27; and 62.6±44.3 days in males vs. 56.5±39 days in females; p=0.15). Mortality was comparable in both groups at 2-year-follow-up (6.8% in males vs. 9.7% in females; p=0.55). Appropriate WCD shocks and the incidence of device implantations were similar in both groups (2.4% in males vs. 3.9% in females; p=0.07) (35.1% in males vs. 31.8% in females; p=0.37), respectively. In age quartile analysis, compliance was observed more in older patients as compared to adult patients (87.8% vs. 68.3%; pConclusion Compliance for wearing WCD was excellent regardless of gender. Furthermore, mortality and the incidence of device implantations were comparable in both groups. Appropriate WCD shocks tended to be higher in females as compared to males.

The development of scalable techniques to make two-dimensional (2D) material heterostructures is a major obstacle that needs to be overcome before these materials can be implemented in device technologies. Electrodeposition is an industrially compatible deposition technique that offers unique advantages in scaling 2D heterostructures. In this work, we demonstrate the electrodeposition of atomic layers of WS2 over graphene electrodes using a single source precursor. Using conventional microfabrication techniques, graphene was patterned to create micro-electrodes where WS2 was site-selectively deposited to form 2D heterostructures. We used various characterization techniques, including atomic force microscopy, transmission electron microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy to show that our electrodeposited WS2 layers are highly uniform and can be grown over graphene at a controllable deposition rate. This technique to selectively deposit transition metal dichalcogenides over microfabricated graphene electrodes paves the way towards wafer-scale production of 2D material heterostructures for nanodevice applications.

After His bundle electrography was established in 1967, the step from invasive electrophysiologic diagnosis of arrhythmias to interventional treatment by catheter ablation was imminent. The time interval of 15 years between the diagnosis and treatment of arrhythmias was even shorter than the 19 years between the first selective coronary angiography in 1958 at the Cleveland Clinic in the USA and the first percutaneous coronary intervention in 1977 in Zurich. During each time period, a great amount of knowledge was gained in cardiac surgery, which proved to be very helpful for the development of the interventional treatment. The history of endovascular treatment is an impressive reminder that the preparation and support of cardiovascular surgeons and their handling of complications played a decisive role in the further development of cardiovascular internal medicine. The history of catheter ablation teaches us that the joint work of cardiologists and cardiovascular surgeons is of great importance for the choice and further development of the best possible treatment as for future development of the techniques of therapy.

Patients with a left ventricular ejection fraction (LVEF) ≤35% should be protected from sudden cardiac death with an implantable cardioverter-defibrillator (ICD). The onset of the effect of optimal medical therapy (OMT) is unclear, and a wearable cardioverter-defibrillator (WCD) can bridge this period.Our study analyzed 104 patients (age, 68.9 ± 11.7 years; 81% [84/104] male) whose first diagnosis included an LVEF35%. After exclusion of reversible causes for LVEF reduction and initiation/adjustment of the OMT, the WCD was employed. The LVEF and indication for ICD were re-evaluated after 62 ± 36 days. The LVEF development and implantation rate were correlated with underlying disease (ischemic [ICM] or nonischemic cardiomyopathy [NICM]), comorbidities, and age/gender.The wearing time of the WCD was 22.8 ± 1.9 h/day. An LVEF improvement from 28.5 ± 6.4% to 40 ± 11.7% was achieved through OMT (p 0.0001). An improvement in LVEF of up to more than 35% was achieved in 66 of 104 patients (63%), and only 37% of patients were subsequently given an ICD. This affected 41% of patients with ICM and 30% of patients with NICM (p = 0.205). Notably, no ICD interventions were observed over 362 ± 89.5 days after implantation in the ICD-receiver group.The indication for ICD can be re-evaluated after 2 months. Patients with NICM respond better to OMT compared with ICM patients. The LVEF recovered to35% in60% of cases.HINTERGRUND: Patienten mit einer linksventrikulären Ejektionsfraktion (LVEF) ≤35 % sollten mit einem implantierbaren Kardioverter-Defibrillator (ICD) vor dem plötzlichen Herztod geschützt werden. Die Dauer bis zum Eintreten der Wirkung der optimalen medikamentösen Therapie (OMT) ist unklar; ein tragbarer Kardioverter-Defibrillator (WCD) kann diese Zeit überbrücken.Insgesamt wurden 104 Patienten (Alter 68,9 ± 11,7 Jahre; 81 % [84/104] männlich) mit erstmals diagnostizierter LVEF35 % analyisiert. Nach Ausschluss reversibler Ursachen für die LVEF-Reduktion und Initiierung und Anpassung der OMT wurde ein WCD (LifeVest®; ZOLL Medical Corporation, Chelmsford, MA, USA)) verordnet. Die LVEF wurde nach 62 ± 36 Tagen reevaluiert und die ICD-Indikation erneut geprüft. Die Entwicklung der LVEF und die Implantationsrate wurden hinsichtlich ihrer Korrelation mit der zugrunde liegenden Herzerkrankung (ischämische [ICM] oder nichtischämische Kardiomyopathie [NICM]), mit Komorbiditäten sowie Alter und Geschlecht analysiert. ICD-Interventionen konnten bei den Patienten, die einen ICD erhielten, über einen Nachsorgezeitraum von 362 ± 89,5 Tagen nicht beobachtet werden.Die Tragezeit des WCD lag bei 22,8 ± 1,9 h/Tag. Die Verbesserung der LVEF von initial 28,5 ± 6,4 % auf 40 ± 11,7 % wurde mithilfe der OMT erreicht (p 0,0001). Eine Verbesserung der LVEF auf bis zu mehr als 35 % wurde bei 66 von 104 Patienten (63 %) beobachtet, daher erfolgte nur bei 37 % der Patienten eine nachfolgende ICD-Implantation. Bei Patienten mit ICM lag die Implantationsrate bei 41 %, bei NICM-Patienten bei 30 % (p = 0,205).Die ICD-Indikation kann bereits nach 2 Monaten OMT reevaluiert werden. Patienten mit NICM sprechen besser auf die OMT an als Patienten mit ICM. Die LVEF verbesserte sich in60 % der Fälle auf35 %.

A graphene field-effect transistor (gFET) was non-covalently functionalised with 1-pyrenebutyric acid N-hydroxysuccinimide ester and conjugated with anti-CD63 antibodies for the label-free detection of exosomes. Using a microfluidic channel, part of a graphene film was exposed to solution. The change in electrical properties of the exposed graphene created an additional minimum alongside the original Dirac point in the drain-source current (Ids) - back-gate voltage (Vg) curve. When phosphate buffered saline (PBS) was present in the channel, the additional minimum was present at a Vg lower than the original Dirac point and shifted with time when exosomes were introduced into the channel. This shift of the minimum from the PBS reference point reached saturation after 30 minutes and was observed for multiple exosome concentrations. Upon conjugation with an isotype control, sensor response to the highest concentration of exosomes was negligible in comparison to that with anti-CD63 antibody, indicating that the functionalised gFET can specifically detect exosomes at least down to 0.1 μg/mL and is sensitive to concentration. Such a gFET biosensor has not been used before for exosome sensing and could be an effective tool for the liquid-biopsy detection of exosomes as biomarkers for early-stage identification of diseases such as cancer.

Here we present an approach to measure the surface potential distribution of specimens using scanning tunnelling potentiometry with high potential gradients and relatively low sample bias. A special design of test structures containing pre-patterned electrodes was employed. Material of interest is transferred onto test structures, so that additional material processing during the investigations can be avoided. The utility of this solution is assessed in an investigation of high–strength metallurgical graphene. A maximum potential gradient of 49.2 V/mm was obtained by applying a sample bias of 0.8 V. Values of the resistivity of graphene inclusions up to 450 Ω·μm were observed. The influence of inclusions could be reduced by performing controllable post-transfer annealing. This could remove polymer residue from the graphene surface, but may introduce additional features in the Raman spectra. Work functions of 4.68–4.70 eV were estimated using Kelvin probe force microscopy.

Introduction Stroke is one of the most feared complications during catheter ablation of atrial fibrillation (AF). While symptomatic thromboembolic events are rare, magnetic resonance imaging (MRI) may identify asymptomatic (ie, silent) cerebral lesions (SCLs) following pulmonary vein isolation (PVI) procedures. Methods and Results The REDUCE‐TE Pilot was a prospective multicenter, single‐arm observational study investigating the incidence of SCL in patients with symptomatic paroxysmal AF undergoing PVI with a novel gold‐tip, externally irrigated ablation catheter. After ablation, cerebral diffusion‐weighted MRI and a postablation follow‐up were performed at 1 to 3 days after the ablation procedure. A neurocognitive test was done before and after ablation. The primary study endpoint was the occurrence of one or more new SCLs. Secondary study endpoints included neurocognitive status, procedural success rate, and periprocedural complications including symptomatic thromboembolic events. A total of 104 patients were enrolled (69% male, mean age: 61.5 ± 9.7 years, mean CHA2DS 2‐VASc score: 1.7 ± 1.2). Postprocedural MRI examination was performed in 97 patients, and in nine of them (9.3%; 95% CI: 4.3‐16.9%) a total of 11 SCLs were detected. Univariate analyses did not reveal any significant predictor for new SCLs. Nonsignificant trends were observed for low activated clotting time during ablation and for international normalized ratio value outside the range of 2 to 3 at ablation. There was no evidence of significant deterioration of neurocognitive function after PVI. In four patients, a pericardial tamponade was noted but all patients fully recovered during follow‐up. Conclusions Ablation of AF using a novel gold‐tip, externally irrigated ablation catheter, resulted in SCLs in approximately one out of 10 patients without a measurable effect on neurocognitive function.

Currently the world is being challenged by a public health emergency caused by the coronavirus pandemic (COVID-19). Extensive efforts in testing for coronavirus infection, combined with isolating infected cases and quarantining those in contact, have proven successful in bringing the epidemic under control. Rapid and facile screening of this disease is in high demand. This review summarises recent advances in strategies reported by international researchers and engineers concerning how to tackle COVID-19 via rapid testing, mainly through nucleic acid- and antibody- testing. The roles of biosensors as powerful analytical tools are emphasized for the detection of viral RNAs, surface antigens, whole viral particles, antibodies and other potential biomarkers in human specimen. We critically review in depth newly developed biosensing methods especially for in-field and point-of-care detection of SARS-CoV-2. Additionally, this review describes possible future strategies for virus rapid detection. It helps researchers working on novel sensor technologies to tailor their technologies in a way to address the challenge for effective detection of COVID-19.

Heterostructures involving two-dimensional (2D) transition metal dichalcogenides and other materials such as graphene have a strong potential to be the fundamental building block of many electronic and optoelectronic applications. The integration and scalable fabrication of such heterostructures are of the essence in unleashing the potential of these materials in new technologies. For the first time, we demonstrate the growth of few-layer MoS

Heterostructures involving two-dimensional (2D) transition metal dichalcogenides and other materials such as graphene have a strong potential to be the fundamental building block of many electronic and opto-electronic applications. The integration and scalable fabrication of such heterostructures is of essence in unleashing the potential of these materials in new technologies. For the first time, we demonstrate the growth of few-layer MoS2 films on graphene via non-aqueous electrodeposition. Through methods such as scanning and transmission electron microscopy, atomic force microscopy, Raman spectroscopy, energy and wavelength dispersive X-ray spectroscopies and X-ray photoelectron spectroscopy, we show that this deposition method can produce large-area MoS2 films with high quality and uniformity over graphene. We reveal the potential of these heterostructures by measuring the photo-induced current through the film. These results pave the way towards developing the electrodeposition method for the large-scale growth of heterostructures consisting of varying 2D materials for many applications., 11 pages and 6 figures

After His bundle electrography was established in 1967, the step from invasive electrophysiologic diagnosis of arrhythmias to interventional treatment by catheter ablation was imminent. The time interval of 15 years between the diagnosis and treatment of arrhythmias was even shorter than the 19 years between the first selective coronary angiography in 1958 at the Cleveland Clinic in the USA and the first percutaneous coronary intervention in 1977 in Zurich. During each time period, a great amount of knowledge was gained in cardiac surgery, which proved to be very helpful for the development of the interventional treatment. The history of endovascular treatment is an impressive reminder that the preparation and support of cardiovascular surgeons and their handling of complications played a decisive role in the further development of cardiovascular internal medicine. The history of catheter ablation teaches us that the joint work of cardiologists and cardiovascular surgeons is of great importance for the choice and further development of the best possible treatment as for future development of the techniques of therapy.

In the randomised TATORT-NSTEMI trial routine thrombus aspiration in comparison with standard percutaneous coronary intervention (PCI) did not reduce the primary endpoint of microvascular obstruction assessed by cardiac magnetic resonance imaging in patients with non-ST-elevation myocardial infarction (NSTEMI). So far, no data on long-term outcome of head-to-head comparisons between both treatment strategies in NSTEMI patients have been reported.The prospective, controlled, multicentre, randomised, open-label TATORT-NSTEMI trial assigned patients with NSTEMI and thrombus-containing lesions to aspiration thrombectomy plus PCI ( n=221) or standard PCI only ( n=219). The primary endpoint of the current analysis was the occurrence of major adverse cardiac events defined as the composite of death, myocardial reinfarction, target vessel revascularisation, and new congestive heart failure at 12-month follow-up. In addition, functional outcome and quality of life were assessed.At one year, major adverse cardiac events occurred in 19 patients in the thrombectomy arm and 29 patients in the standard PCI group (8.7% vs. 13.4%, relative risk 0.63, 95% confidence interval 0.35-1.12, p=0.11). The individual components of the combined endpoint such as death ( p=0.20), myocardial reinfarction ( p=0.73), target vessel revascularisation ( p=0.42), and congestive heart failure ( p=0.18) were similar in both groups. Functional outcome and quality of life did not differ significantly between both groups (Canadian Cardiovascular Society class: p=0.68, New York Heart Association class: p=0.70 and EuroQol5D score: p=0.96). Post-hoc analyses revealed consistent results with regard to the occurrence of major adverse cardiac events across a wide range of subgroups (all p0.05).In this first randomised trial on thrombectomy in NSTEMI patients, routine thrombus aspiration before PCI did not improve clinical outcome at 12-month follow-up.

In this work we present combined Kelvin probe force microscopy and Raman spectroscopy studies of supported and suspended structures formed out of chemical vapor deposition (CVD) grown graphene. Work function of both suspended and supported graphene was -4.81 ± 0.06eV and -4.92 ± 0.06eV respectively. By G and 2D modes correlation we showed, that CVD graphene was influenced by biaxial strain. Increased contact potential difference (CPD) on the suspended graphene in comparison with the areas of the supported graphene was the sign of increased strain (from 0.05% to ~ 0.12%) rather than decreased doping (p-doping decreased from ~ 5.5 × 1012cm-2 to ~ 4.5 × 1012cm-2).

Aims We aimed to assess the safety and performance of a novel sirolimus-eluting stent with biodegradable polymer under real-world conditions. Methods and results This prospective, multicentre, observational, all-comers registry enrolled 1,356 patients. The primary endpoint was target lesion failure at 12 months: it occurred in 5.1% (95% CI: 4.0-6.4) of patients in the overall population and in 7.7% (95% CI: 5.5-10.9), 5.8% (95% CI: 4.2-8.1), 1.8% (95% CI: 0.2-11.8) and 7.2% (95% CI: 5.1-10.0) of patients with diabetes mellitus, small vessels, chronic total occlusion and acute myocardial infarction, respectively. Conclusions This novel stent platform demonstrated good clinical outcomes in an all-comers population, even in predefined high-risk groups. ClinialTrials.gov identifier: NCT01553526

Background The impact of right ventricular (RV) lead location on clinical end points in patients undergoing cardiac resynchronization therapy (CRT) is unclear. We evaluated the impact of different RV lead locations on clinical outcome in CRT patients enrolled in the Septal Positioning of ventricular implantable cardioverter-defibrillator (ICD) Electrodes (SPICE) trial, which randomized recipients of implantable cardioverter defibrillators to apical versus midseptal RV lead positioning. Methods Ninety-eight CRT recipients were included in the multicenter SPICE trial and followed for 12 months: Fifty-three patients were randomized to receive an apical (A) and 45 to receive a midseptal (S) lead position. We compared echocardiographical and electrocardiographical parameters and outcome. Results Echocardiographic response with respect to improvement of left ventricular ejection fraction (A: +15.8 ± 14.6%, S: +9.7 ± 12.6%, P = 0.156) and reduction of left ventricular end-diastolic diameter (A: −4.2 ± 10.7 mm, S: −7.5 ± 10.7 mm, P = 0.141) was comparable in apical and midseptal groups. Paced QRS width neither differed at prehospital discharge (A: 129 ± 21 ms, S: 135 ± 21 ms, P = 0.133) nor at 12-month follow-up (A: 131 ± 23 ms, S: 134 ± 28 ms, P = 0.620). No differences were found with respect to the risk of ventricular tachyarrhythmia or ICD therapy. Septal RV lead position, however, was associated with a significant longer time to a first heart failure event (P = 0.040) and a longer survival time (P = 0.019). Conclusions In CRT recipients, midseptal RV lead position was not superior with respect to improvement of echocardiographic parameters or paced QRS width. It did not predispose to ventricular arrhythmias or ICD therapy. The finding that midseptal lead position was associated with a longer time to first heart failure event and a longer survival time deserves further investigation.

Van der Waals mono- and heterostructures have received great attention in recent years due to their new physics and electronic properties. Several novel device structures have been developed based on their properties, including tunnelling transistors, light emitting diodes and barristors. However, the construction of such structures usually involves transfer techniques which could induce damage and modify the electronic properties of the structures and degrade device performance. Here we show that a multi-step transfer process for graphene may disturb its transport properties at microscale. Bilayer graphene was transferred, using PMMA as supporting material, onto an Al2O3/Si substrate with pre-patterned chromium-palladium electrodes. Using scanning tunnelling potentiometry, we observed that the local potential gradient (and resulting current flow) significantly changed compared with the potential gradient arising from the electrodes’ position and biasing. This could be attributed to local material ad-layers, unspecified contact or additives present between sub-layers. This finding represents an important step in understanding the effect of transfer techniques on the quality of multilayer van der Waals mono- and heterostructures.

Recent experimental results for the gravitational constant G from Cavendish-type experiments were analysed in the framework of Modified Newtonian Dynamics (MOND). MOND corrections were applied to the equation of motion of a pendulum, under the assumption that the magnitude of the horizontal time dependent gravitational acceleration determines the amount of MOND corrections. The large vertical component of the local gravitational field of the earth is fully compensated by the alignment of the torsion pendulum in accordance with Newtons third law and therefore not considered for MOND corrections. From the analysis of the MOND corrected equation of motion of a realistic torsion pendulum with mixed gravitational and electromagnetic restoring torque simple rules for meaningful MOND corrections of measured G values determined by different operational modes of Cavendish type G experiments were derived. Based on this analysis the reported discrepancies for G determined by static deflection and electrostatic servo methods of the BIPM experiment by Quinn et al. and between time-of-swing and angular acceleration feedback methods for the HUST experiment by Li et al. could be fully resolved by MOND corrections using one common MOND interpolation function, determined by a one parameter fit. The MOND corrected BIPM and HUST results, along with other single method results from G experiments by Gundlach and Merkovitz, Schlamminger et al. and Newman et al. lead to an average G value of 6.67422x10^-11 m^3 kg^-1 s^-2 with a standard deviation of 12.5 ppm only. The applied MOND correction procedure and the fitted interpolation function employed for the G experiments were found to be consistent with the most viable MOND fits to galaxy rotation curves., 22 pages, 7 figures. 2020 Class. Quantum Grav

The self-supporting monolayer material which is graphene has excited enormous interest over the ten years since its discovery due to its remarkable electrical, mechanical thermal and chemical properties. In this paper we describe our work to develop chemical vapour deposition methods to grow monolayer graphene on copper foil substrates and the subsequent transfer process. Raman microscopy, scanning electron microscopy and atomic force microscopy (AFM) are used to examine the quality of the transferred material. To demonstrate the process we describe transfer onto patterned SiO2/Si substrates which forms freely suspended graphene with focus on circular wells forming graphene drums. These show interesting mechanical properties which are being explored as nanomechanical resonators. UK NMS Programme, the EU EMRP (European Metrology Research Programme) projects MetNEMS and GraphOhm

Aims Right ventricular (RV) septum is a non-apical site targeted during lead implantation. Electrocardiographic (ECG) recognition of mid-septal lead location is challenging. The aim of the study is to determine ECG correlates of RV mid-septal pacing. Methods and results The present study is a pre-specified analysis of a prospective, multicenter study, which randomized recipients of an implantable cardioverter defibrillator to an apical vs. mid-septal RV lead positioning. Following implantation, a 12-lead ECG was recorded during intrinsic rhythm and RV pacing. In total, 227 patients, 121 in the apical group (76.9% males, 67.1 ± 11.3 years) and 106 in the mid-septal group (82.1% males, age 64.7 ± 12.7 years) were included. Apically as compared with septally paced patients had significantly longer paced QRS duration (177.0 ± 25.0 vs. 170.4 ± 21.7, respectively, P = 0.03) and significantly more leftward paced QRS axis (−71.6 ± 33.3° vs. 9.4 ± 86.5°, respectively, P < 0.001). A significantly higher proportion of patients in the mid-septal as compared with the apical group displayed predominantly positive QRS in lead V6 (62.3 vs. 4.1%, P < 0.001), predominantly positive QRS in any of the inferior leads (53.8 vs. 4.1%, P < 0.001), and a QR pattern in lead aVL (53.3 vs. 3.3%, P < 0.001). These ECG correlates were incorporated in a stepwise algorithm with total sensitivity of 87% and specificity of 90% for the identification of a mid-septal lead location. Conclusion A mid-septal lead location may be identified using a simple stepwise algorithm, based on the presence of positive QRS in lead V6, positive QRS in any of the inferior leads, and a QR pattern in lead aVL.

Electrocardiographic (ECG) identification of prior myocardial infarction (MI) during right ventricular (RV) pacing is of clinical importance. Proposed ECG criteria have been evaluated only during apical pacing. We evaluated the effect of pacing site on the predictive performance of ECG signs of prior MI.The present study is a secondary analysis of a prospective, multicenter study which randomized recipients of an implantable cardioverter defibrillator to an apical versus septal RV lead positioning. ECGs of patients with or without prior MI were analyzed for the presence of the following criteria: Cabrera sign, Chapman sign, QR pattern in leads I, aVL, V5 or V6, QR in inferior leads and notching in the descending slope of the QRS complex in inferior leads.The MI group included 89 patients (55.1% apically paced), while 99 patients had no prior MI (50.5% apically paced). In the total population, the Cabrera sign presented the highest specificity (97%) and diagnostic accuracy (62.2%), with a sensitivity of 23.6%. The Cabrera sign was the only significant predictor of a prior MI [OR=9.9, (95%CI:2.8-34.5), p0.001], among all ECG markers. Pacing site did not significantly influence the sensitivity and specificity of the Cabrera sign for detection of prior MI.In our study, the Cabrera sign was the only ECG marker that predicted the presence of prior MI during ventricular paced rhythm. Septal RV lead positioning did not affect the predictive performance of the Cabrera sign.

We present a highly sensitive microfluidic sensing technique for the terahertz (THz) region of the electromagnetic spectrum based on spoof surface plasmon polaritons (SPPs). By integrating a microfluidic channel in a spoof SPP waveguide, we take advantage of these highly confined electromagnetic modes to create a platform for dielectric sensing of liquids. Our design consists of a domino waveguide, that is, a series of periodically arranged rectangular metal blocks on top of a metal surface that supports the propagation of spoof SPPs. Through numerical simulations, we demonstrate that the transmission of spoof SPPs along the waveguide is extremely sensitive to the refractive index of a liquid flowing through a microfluidic channel crossing the waveguide to give an interaction volume on the nanoliter scale. Furthermore, by taking advantage of the insensitivity of the domino waveguide’s fundamental spoof SPP mode to the lateral width of the metal blocks, we design a tapered waveguide able to achieve further confinement of the electromagnetic field. Using this approach, we demonstrate the highly sensitive detection of individual subwavelength micro-particles flowing in the liquid. These results are promising for the creation of spoof SPP based THz lab-on-a-chip microfluidic devices that are suitable for the analysis of biological liquids such as proteins and circulating tumour cells in buffer solution.

Fatty-add binding proteins (FABP) and myeloperoxidases (MPO) are associated with many chronic conditions in humans and considered to be important biomarkers for diagnosis of cardiac diseases. Here we assemble a new electrical biosensor platform based on graphene-coated interdigitated electrode arrays (IDE-arrays) towards ultrafast, label-free screening of heart type-FABP and MPO. Arrays of nanoscale (nanoIDE) and microscale (microIDE) electrode-arrays were fabricated on wafer-scale by combining nanoimprint and photolithography processes. Chemical vapor deposition grown multilayer graphene was transferred onto nano/microIDE-arrays and used as a high surface-to-volume ratio electrical transducer. Novel biofunctional layers of specially engineered anti-h-FABP and anti-MPO single-chain fragment variables (scFv) were immobilized onto graphene-coated IDE-array sensor platform for electrical detection of h-FABP and MPO in physiological saline. scFv fragments show increased sensitivity in comparison to the state-of-the-art competitive ELISA for their higher affinity towards target analytes. Deploying FABP and MPO specific scFvs as receptor molecules onto our high sensitivity graphene-coated IDE-arrays with identical sensor characteristics and assays covering clinically relevant concentrations in physiological saline, we demonstrate realization of a simple and versatile biosensor platform capable of high performance cardiac-bioassays for point-of-care applications. Stiftung Rheinland-Pfalz fur Innovation [1082]; Euroimmun AG; European Commission FP7 Programme through the Marie Curie Initial Training Network PROSENSE [317420]; DCU INVENT; Imperial sources

Scientific Reports 6: Article number: 22858; published online: 09 March 2016; updated: 13 February 2017 This Article contains errors in Figure 4, where the left (θL) and right (θR) angles are incorrectly defined. The correct Figure 4 appears below as Figure 1.

Metallic gate electrodes are often employed to control the conductivity of graphene based field effect devices. The lack of transparency of such electrodes in many optical applications is a key limiting factor. We demonstrate a working concept of a double layer graphene field effect device that utilizes a thin film of sputtered aluminum nitride as dielectric gate material. For this system, we show that the graphene resistance can be modified by a voltage between the two graphene layers. We study how a second gate voltage applied to the silicon back gate modifies the measured microwave transport data at around 8.7 GHz. As confirmed by numerical simulations based on the Boltzmann equation, this system resembles a parallel circuit of two graphene layers with different intrinsic doping levels. The obtained experimental results indicate that the graphene-aluminum nitride-graphene device concept presents a promising technology platform for terahertz- to- optical devices as well as radio-frequency acoustic devices where piezoelectricity in aluminum nitride can also be exploited.

Background: In an earlier study comparing acceleration sensor (AS)- and closed loop stimulation (CLS)-based rateadaptive pacing, a sub analysis showed that heart rate (HR) after 6-minute walk (6MW) was higher in symptomatic (NYHA II/III) than symptom-free (NYHA I) patients in the CLS group only. The present study evaluated prospectively whether CLS unlike AS is able to differentiate between symptomatic and symptom-free patients, for whom 6MW represents demanding exercise versus low-to-moderate exercise, requiring marked versus moderate HR increase, respectively. Methods: The study randomized 205 chronotropically incompetent patients 1:1 to AS or CLS. Primary endpoint was HR after 6MW for symptomatic versus symptom-free patients in each randomization group. A subanalysis tested primary endpoint only in patients with heart failure (HF). Secondary endpoint was HF progression over 2 years. Results: The primary endpoint showed the expected tendency without statistical significance. In the subanalysis, HR after 6MW was significantly higher in symptomatic than symptom-free patients for CLS sensor (median, 92 vs. 84 bpm [P=0.021]), with an opposite non-significant trend for AS. HF development did not differ significantly between AS and CLS. Conclusions: CLS increased HR more selectively than AS in symptomatic patients with HF. Progression of HF over 2 years was minimal in both modes.