Direct Ablation Research Articles

Inflammation and long-term outcomes after first-time direct current cardioversion for atrial fibrillation: a nationwide register study

Abstract Background Emerging evidence suggests that the pathogenesis of atrial fibrillation (AF) is affected by inflammatory processes which contribute to structural and electrical remodeling of the atria, creating a substrate for arrythmia. Aim To assess whether inflammation measured by C-reactive protein (CRP) is associated with readmission for direct current (DC) cardioversion, ablation, heart failure or stroke after discharge from 1st time DC cardioversion. Methods This nationwide retrospective cohort study included patients undergoing 1st DC cardioversion between 2011 and 2018. Exclusion criteria were death within one day of cardioversion and no available CRP at baseline. Primary outcome was readmission for DC cardioversion of AF. Secondary outcomes were AF ablation, new admission of stroke, new admission of heart failure (HF), and all-cause death. Absolute risk rates (ARR) of outcomes were calculated for patients with available 1-year follow-up data. CRP 20 mg/L was chosen as cutoff to establish a clinically relevant borderline for inflammation. The association between baseline CRP and outcome was assessed in Cox proportional hazards regression models with a follow-up period starting from 1st DC cardioversion, ending no later than 31st of December 2018, for the entire study population (n=9,977). Results After exclusion criteria the study population consisted of 9,977 patients Mean age for CRP > 20mg/L: 66.8 (IQR: 60.5-74.2). Mean age for CRP < 20mg/L 68.9 (IQR: 62.9-75.9)(p<0.001). In total, 68.9% were male and the most frequent comorbidities included hypertension (57.3%), ischemic heart disease (25.1%), HF (20.6%), and history of stroke (7.1%). Patients with available CRP measurement and 1yr follow up was 7,764. Compared to patients with low CRP (<20 mg/L), patients with elevated CRP (>20mg/L) had a higher 1-year ARR of HF, and all cause death (p<0.001). Compared to patients with low CRP, patients with elevated CRP had a lower 1-year ARR of all-ablation and new DC cardioversion (p<0.001), (Table 1). CRP > 20mg/L was associated with lower risk for new DC cardioversion (HR 0.72, 95% CI: 0.64-0.82, p<0.001). However, in patients <75 years of age with CRP > 20mg/L at baseline had an increased risk of stroke after multivariable adjustments (HR 1.92, 95% CI: 1.10-3.35; p = 0.02) (Fig.1), while CRP > 20 mg/L was not associated with an increased risk of stroke in patients > 75yrs of age (Cox regressions estimates) (p for interaction = 0.03). Conclusion However, elevated CRP was associated with an increased risk of stroke in patients <75 years of age, even after multivariable adjustments. These results suggest that CRP may not be a reliable predictor of readmission for DC-cardioversion, especially in older individuals, but might be a potential risk stratification tool in identifying AF patients at higher risk of stroke in young individuals. We suspect this is due to the population with elevated CRP has more comorbidities and are older.

Picosecond pulsed laser scribing of Cd2SnO4-based CdTe thin-film solar cells on flexible glass

CdTe photovoltaic modules are the most commercially successful thin-film solar cells. In particular, flexible CdTe modules are a promising development in photovoltaic architecture. Cd2SnO4 (CTO) is a low-cost transparent conductive material with excellent optical and electrical properties. Although laser scribing is commonly used to produce cell interconnects in the manufacturing of thin-film PV modules, the laser scribing process window for CTO-based CdTe cells is narrow, and more research is needed on direct laser scribing of flexible CdTe solar cells. In this study, the picosecond pulsed laser scribing of CdTe solar cells with CTO front electrodes and flexible glass substrates was investigated using lasers with the wavelengths of 355 and 532 nm. The flexible cells were suctioned onto a working platform, and a direct ablation method was adopted. The damage and removal thresholds of the CTO, CdTe, and Ni layers were studied and the effects of the spot spacing, multilayer conditions, and laser polarization state were investigated. A method for determining the scribing parameters was proposed. Very smooth scribing grooves were obtained using the optimized laser scribing process. The series and shunt resistances of the cells after laser scribing showed no significant differences compared to those of the control cells.

Laser-Induced Breakdown Spectroscopy as an Accurate Forensic Tool for Bone Classification and Individual Reassignment.

This article provides a detailed discussion of the evidence available to date on the application of laser-induced breakdown spectroscopy (LIBS) and supervised classification methods for the individual reassignment of commingled bone remains. Specialized bone chemistry studies have demonstrated the suitability of bone elemental composition as a distinct individual identifier. Given the widely documented ability of the LIBS technique to provide elemental emission spectra that are considered elemental fingerprints of the samples analyzed, the analytical potential of this technique has been assessed for the investigation of the contexts of commingled bone remains for their individual reassignment. The LIBS bone analysis consists of the direct ablation of micrometric portions of bone samples, either on their surface or within their internal structure. To produce reliable, accurate, and robust bone classifications, however, the available evidence suggests that LIBS spectral information must be processed by appropriate methods. When comparing the performance of seven different supervised classification methods using spectrochemical LIBS data for individual reassociation, those employing artificial intelligence-based algorithms produce analytically conclusive results, concretely individual reassociations with 100% accuracy, sensitivity, and robustness. Compared to LIBS, other techniques used for the purpose of interest exhibit limited performance in terms of robustness, sensitivity, and accuracy, as well as variations in these results depending on the type of bones used in the classification. The available literature supports the suitability of the LIBS technique for reliable individual reassociation of bone remains in a fast, simple, and cost-effective manner without the need for complicated sample processing.

Femtosecond laser-induced plasma-assisted backward deposition of robustly adherent porous carbon films on glass substrates

The simple and rapid production and transfer of high-quality carbon materials are crucial for the flexible and efficient fabrication of carbon-based electronic devices. Recently, a laser-assisted transfer method combining laser-induced carbonization and transfer printing was demonstrated for the one-step preparation and transfer of patterned laser-induced carbon films to transparent substrates. However, this method is limited by insufficient robustness and weak adhesion of the carbon film post-transfer. Herein, we developed a non-contact laser-induced plasma-assisted deposition method to deposit robustly adherent porous carbon films on glass substrates. By well-adjusting the laser parameters and inserting spacers with adjustable thickness, laser-induced plasma ablation replaced direct laser ablation during femtosecond laser scanning of the substrate-polyimide-carrier sandwich structure, resulting in micro-channels with a carbon-glass recast layer instead of easily peelable flakes on the glass substrate. This hierarchical structure significantly enhances the adhesion between the laser-induced carbon film and the glass substrate, ensuring outstanding stability of the deposited carbon film under various adhesion tests. Furthermore, compared to carbon films prepared by the laser-assisted transfer method, the obtained carbon films are hydrophilic, low-resistance, and porous, facilitating the fabrication of energy storage devices. To demonstrate its practical application, a planar carbon-based micro-supercapacitor was fabricated on glass, exhibiting excellent electrochemical and cycling performance.

Tumor Metabolism Aiming Cu2-xS Nanoagents Mediate Photothermal-Derived Cuproptosis and Immune Activation.

Cuproptosis is an emerging form of cell death that relies on the targeted delivery of copper ions to lipoylated tricarboxylic acid cycle proteins. However, a major challenge associated with cuproptosis is its potential to kill both normal and tumor cells without discrimination. Therefore, it is crucial to develop strategies for precise intracellular delivery and redox control of copper to create effective cuproptosis-based tumor therapies. We have introduced a class of nanoagents called metabolism aiming Cu2-xS (MACuS) through a glucose-mediated biomineralization approach. MACuS nanoagents can be specifically targeted to tumors via the glucose transport receptor 1, and we found that NIR-II irradiation can not only result in direct hyperthermia ablation of tumor cells but also facilitate efficient cuproptosis and enhance reactive oxygen species-induced cytotoxicity in tumor cells. As a result, the triple effect of MACuS treatment induced immunogenic cell death, which triggered systemic antitumor immune responses and demonstrated potent efficacy in inhibiting growth, metastasis, and recurrence in mouse and rabbit breast cancer models. The precise intracellular delivery and redox control of copper provided by MACuS hold great potential for the development of highly efficient cuproptosis-based tumor therapies with minimal off-target effects.

Quantitative Measurement of Multiple Elements in Micro‐Quantities of Crude Oil Using In Situ Analysis by Laser Ablation‐ICP‐MS

Multi‐element quantification in small amounts of material and in situ measurements at the micrometre scale are essential aspects of geological sample investigation. A direct and rapid simultaneous multi‐elemental determination of metals in crude oil samples was carried out by combining direct laser ablation of the oil inserted in silica capillaries with inductively coupled plasma‐mass spectrometry. The accuracy of LA‐ICP‐MS determination was demonstrated by analysing CONOSTAN reference material oils, certified for multiple elements, and by comparing LA‐ICP‐MS measurement results with those obtained by ICP‐OES using microwave‐assisted sample digestion. The results obtained by both methods were in agreement with certified values. The LA‐ICP‐MS method showed an adequate precision with a mean relative standard deviation of less than 10% for multi‐element determination, and was sufficiently sensitive to determine the majority of elements. LA‐ICP‐MS was also applied to the determination of elements in crude oils of different origins. LA‐ICP‐MS is a good alternative method allowing the determination of elements in organic fluids (oil and bitumen) in shorter times, involving less material consumption, smaller test portion size and with higher throughput compared with protocols using, for instance, sample digestion. It validates the possible application of metal analysis in hydrocarbon‐containing fluid inclusions for metallogenic purposes.

Coating-assisted picosecond laser ablation for microstructure fabrication of SiC ceramics

Silicon carbide (SiC) ceramics have emerged as critical materials in the production of high-precision components. Ultrafast laser processing is deemed the optimal technique for micro-nano manufacturing of SiC. However, the permanent deposition layer induced by laser ablation can critically impact the precision of the component. In this work, a coating-assisted picosecond laser ablation (CAPLA) method was proposed, in which sacrificial photoresist coating was utilized to improve surface quality without efficiency loss. The coating serves to prevent the uncooled plasma from contacting with the substrate, thereby preventing the formation of a permanent deposition layer. By comparing the CAPLA method with laser direct ablation, the influence of laser parameters and photoresist coating characteristics on the deposition layer was investigated systematically. A processed surface devoid of deposition layers can be achieved by CAPLA with low pulse energy and a high number of scans. The uniformity is critical to ensure the transmission of the laser beam, and a larger thickness can improve the processing efficiency by increasing the limit of pulse energy capacity. Pin arrays and vacuum grooves for SiC ceramic vacuum chucks were fabricated to demonstrate the superiority of the CAPLA method. These results suggest that this method can be a novel and promising approach for high-precision component manufacturing.

Adjunctive left atrial posterior wall isolation for atrial fibrillation: An updated systematic review and meta-analysis.

Posterior left atrial wall isolation (PWI) plus traditional pulmonary vein isolation (PVI) has been proposed as a promising intervention to decrease atrial fibrillation (AF) recurrence. We aim to investigate the efficacy and safety of adding PWI to the traditional PVI in patients with AF. A systematic review and meta-analysis was conducted using synthesizing randomized controlled trials (RCTs) retrieved by systematically searching PubMed, Web of Science, SCOPUS, EMBASE, and Cochrane through June 14, 2023. We used Stata version 17 to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD), with a 95% confidence interval (CI) (PROSPERO ID: CRD42023446227). We included 11 RCTs with a total number of 1534 patients. Combined ablation with PWI + PVI was not associated with any significant difference over PVI only regarding the recurrence of clinical AF (RR: 0.86 with 95% CI [0.70-1.06]), all atrial arrhythmia (RR: 0.93 with 95% CI [0.82-1.07]), nonatrial fibrillation arrhythmia (RR: 1.22 with 95% CI [0.97-1.53]), early AF (RR: 0.89 with 95% CI [0.62-1.27]), and antiarrhythmic drugs at discharge (RR: 0.83 with 95% CI [0.67-1.04]). However, it was associated with increased total ablation duration (minutes) (MD: 12.58 with 95% CI [6.80-18.37]) and total procedure duration (minutes) (MD: 16.77 with 95% CI [9.63-23.91]), without any significant difference regarding adverse events (RR: 1.05 with 95% CI [0.63-1.74]). While the pooled data from PWI + PVI using point-by-point radiofrequency did not suggest a benefit in the recurrence of various atrial arrhythmias compared to PVI alone, PWI+PVI using direct posterior wall ablation, especially with cryoballoon, demonstrated a significant reduction in recurrence of AF/atrial arrhythmias. Also, PWI + PVI significantly increased the ablation and total procedure durations.

RIPPLE-VT study: Multicenter prospective evaluation of ventricular tachycardia substrate ablation by targeting scar channels to eliminate latest scar potentials without direct ablation

BackgroundRecurrent ventricular tachycardia (VT) can be treated by substrate modification of the myocardial scar by catheter ablation during sinus rhythm without VT induction. Better defining this arrhythmic substrate could help improve outcome and reduce ablation burden. ObjectiveThe study aimed to limit ablation within postinfarction scar to conduction channels within the scar to reduce VT recurrence. MethodsPatients undergoing catheter ablation for recurrent implantable cardioverter-defibrillator therapy for postinfarction VT were recruited at 5 centers. Left ventricular maps were collected on CARTO using a Pentaray catheter. Ripple mapping was used to categorize infarct scar potentials (SPs) by timing. Earliest SPs were ablated sequentially until there was loss of the terminal SPs without their direct ablation. The primary outcome measure was sustained VT episodes as documented by device interrogations at 1 year, which was compared with VT episodes in the year before ablation. ResultsThe study recruited 50 patients (mean left ventricular ejection fraction, 33% ± 9%), and 37 patients (74%) met the channel ablation end point with successful loss of latest SPs without direct ablation. There were 16 recurrences during 1-year follow-up. There was a 90% reduction in VT burden from 30.2 ± 53.9 to 3.1 ± 7.5 (P < .01) per patient, with a concomitant 88% reduction in appropriate shocks from 2.1 ± 2.7 to 0.2 ± 0.9 (P < .01). There were 8 deaths during follow-up. Those who met the channel ablation end point had no significant difference in mortality, recurrence, or VT burden but had a significantly lower ablation burden of 25.7 ± 4.2 minutes vs 39.9 ± 6.1 minutes (P = .001). ConclusionScar channel ablation is feasible by ripple mapping and can be an alternative to more extensive substrate modification techniques.

Comparative Efficacy and Safety of Pulsed Field Ablation Versus Radiofrequency Ablation of Idiopathic LV Arrhythmias

BackgroundComparative efficacy and safety data on radiofrequency ablation (RFA) versus pulsed field ablation (PFA) for common idiopathic left ventricular arrhythmia (LV-VAs) locations are lacking. ObjectivesThis study sough to compare RFA with PFA of common idiopathic LV-VAs locations. MethodsTen swine were randomized to PFA or RFA of LV interventricular septum, papillary muscle, LV summit via distal coronary sinus, and LV epicardium via subxiphoid approach. Ablations were delivered using an investigational dual-energy (RFA/PFA) contact force (CF) and local impedance-sensing catheter. After 1-week survival, animals were euthanized for lesion assessment. ResultsA total of 55 PFA (4 applications/site of 2.0 KV, target CF ≥10 g) and 36 RFA (CF ≥10 g, 25–50 W targeting ≥50 Ω local impedance drop, 60-second duration) were performed. LV interventricular septum: average PFA depth 7.8 mm vs RFA 7.9 mm (P = 0.78) and no adverse events. Papillary muscle: average PFA depth 8.1 mm vs RFA 4.5 mm (P < 0.01). Left ventricular summit: average PFA depth 5.6 mm vs RFA 2.7 mm (P < 0.01). Steam-pop and/or ventricular fibrillation in 4 of 12 RFA vs 0 of 12 PFA (P < 0.01), no ST-segment changes observed. Epicardium: average PFA depth 6.4 mm vs RFA 3.3 mm (P < 0.01). Transient ST-segment elevations/depressions occurred in 4 of 5 swine in the PFA arm vs 0 of 5 in the RFA arm (P < 0.01). Angiography acutely and at 7 days showed normal coronaries in all cases. ConclusionsIn this swine study, compared with RFA, PFA of common idiopathic LV-VAs locations produced deeper lesions with fewer steam pops. However, PFA was associated with higher rates of transient ST-segment elevations and depressions with direct epicardium ablation.

Repetitive high-power discharge operation of a micro-laser triggered gas switch.

A low-energy, diode-pumped, solid-state passively Q-switched laser operating at a wavelength of 1535nm has been demonstrated to trigger gas switches. This technology has the potential to bring significant improvements to the operation and reliability of compact pulsed power drivers. Compact pulsed power drivers are often required to operate for hundreds to thousands of shots without maintenance; thus, the reliable operation of the laser triggered switch is significant for the adoption of this technology. A primary limiter of spark gap lifetime is electrode erosion. In the case of a laser triggered switch where the laser is focused on one electrode, an additional source of erosion is the direct ablation of the electrode material by the laser. The micro-laser used in the previous experiments is very low energy, but over thousands of shots, it does damage directly to the target electrode. This damage could potentially interact with the erosion due to the current discharge and impact the operation of the switch. The focus of this paper is to describe experiments undertaken to assess this damage and quantify its effect on switch operation over many discharges at current and energy levels relevant to compact pulsed power systems.

Predicting left atrial appendage thrombus in patients with persistent atrial fibrillation or flutter and no oral anticoagulation using machine-learning models

Abstract Background Atrial fibrillation and flutter (AF/AFL) increase the risk of thromboembolic events by promoting the formation of a left atrial appendage thrombus (LAT). We previously developed artificial intelligence (AI) models to predict LAT based on data from the multicentre, prospective LATTEE registry (Left Atrial Thrombus on Transoesophageal Echocardiography, n= 2489) establishing the utility of AI for identifying the presence of LAT. While our model is now available as an online calculator to date there is no data regarding the utility of our AI in guiding cardioversion in haemodynamically stable patients with persistent arrhythmia and no prior oral anticoagulation (OAC). Purpose To assess the performance of AI decision support to perform TOE or readmit the patient after at least 3 weeks of OAC. Methods In this study, we applied the LAT-AI model (based on 39 features) and the LAT-AI reduced model (based on 8 features) to patients with no or insufficient prior OAC, who underwent TOE before direct current cardioversion or catheter ablation (n=311). We excluded patients with paroxysmal arrhythmia, resulting in a final cohort of 150 patients originating from four sites. We investigated the sensitivity and specificity of the respective models to predict LAT based on the score thresholds established in previous studies (0.37 for the LAT-AI and 0.34 for the LAT-AI reduced). Results The median age in the external cohort was 66 (interquartile range 56-73), 59% were male, and 7.3% had AFL. LAT was found in 17 patients (11%). The LAT-AI model achieved 100% sensitivity (confidence interval [CI]: 40-100) and 12% specificity (95% CI: 7-18). The LAT-AI reduced model achieved 100% sensitivity (95% CI: 87-100) and 14% specificity (95% CI: 8-21). By applying the score threshold which has been derived in our prior studies for the the LAT-AI reduced model, the TOE-first approach would be chosen in 18% and no LAT would be found in this group, while the remaining 82% would be recommended for 3 weeks of OAC before TOE. Such approach could be used to identify patients at low risk of LAT to undergo TOE despite the lack of prior OAC, while the remaining patients at higher risk of LAT could potentially avoid repeated TOE thanks to the 3-week course of OAC before the first TOE. Conclusion AI scores allow high sensitivity for prediction of the presence of LAT in patients with AF/AFL irrespective of OAC treatment and have the potential to optimise the management of patients with indications for elective cardioversion and no prior or ineffective OAC.Simulated AI-supported decisionScreenshot of the online app

Development of a facile, versatile and scalable fabrication approach of solid, coated, and dissolving microneedle devices for transdermal drug delivery applications

Nowadays, microneedles as novel transdermal delivery systems are interested in scientists for biomedical applications. This work aims to present a Cascade Microneedle Molding Technique (CMMT) for the reusable fabrication of polydimethylsiloxane (PDMS) molds to produce microneedle devices. To produce a positive master mold from epoxy resin, a negative PDMS mold was first fabricated. PDMS can be molded, and microneedles can be fabricated using this epoxy mold in a scalable and cost-effective manner. These molds were used to manufacture solid, coated, and dissolving microneedles, which were characterized comprehensively. Microneedle morphology and geometry were evaluated using Scanning Electron Microscopy (SEM). The mechanical integrity and ability to insert the microneedle device into the skin were assessed using compression strength analysis and force-displacement measurements. Drug penetration through animal skin was evaluated for Rhodamine B (RhB) loaded microneedles. The depth of needle insertion was also visualized using histological analysis while the spatial distribution of released cargo was determined by using confocal microscopy. Taken together, CMMT offers a simple, rapid, cost-effective, and scalable method for mass-producing microneedles with remarkable properties compared to direct 3D printing or laser ablation.

Development of non-invasive flexible directional microwave ablation for central lung cancer: a simulation study

Transbronchial microwave ablation (MWA) with flexible antennas has gradually become an attractive alternative to percutaneous MWA for lung cancer due to its characteristic of non-invasiveness. However, flexible antennas for the precision ablation of lung tumors that are adjacent to critical bronchial structures are still not available. In this study, a non-invasive flexible directional (FD) antenna for early stage central lung tumors surrounding the bronchia was proposed. A comprehensive numerical MWA model with the FD antenna was developed in a real human-sized left lung model. The structure of the antenna and the treatment protocol were optimized by a generic algorithm for the precision ablation of two cases of early stage central lung cancer (i.e. spherical-like and ellipsoidal tumors). The electromagnetic efficiency of the optimized antenna was also improved by implementing an optimized π -matching network for impedance matching. The results indicate that the electromagnetic energy of MWA can be restricted to a particular area for precision ablation of specific lung tumors using the FD antenna. This study contributes to the field of lung cancer management with MWA.

THz active modulation device by electric field turned modulation characteristics of titanium sulfide nanofilm device

AbstractAn effective approach to manipulate terahertz (THz) waves involves the utilization of a device structure. In this particular investigation, we have successfully fabricated a SnS2 nanofilm device using femtosecond laser direct ablation. The passive and active polarization‐sensitive characteristics of the SnS2 nanofilm device were examined within the THz frequency range, employing different line spaces of 500, 600, and 700 μm. The combination of the device effect and SnS2 absorption led to an enhanced passive polarization modulation. Moreover, when an external electric field was applied to the SnS2 nanofilm device along the device line, persistent switching and linear modulation of THz wave transmission were observed. These findings indicate that the integration of material properties and device structure in this SnS2 device renders it highly suitable for applications in ultrafast THz switches, filters, and modulation devices.

Thinning and dynamics of the glacier terminus at the Pasterze Glacier (Austria), 2016–2021

As a result of global warming, glaciers worldwide recede and lose mass. Glacier ablation is influenced by surface characteristics, in particular the existence of debris cover. The evolution of glaciers may also be influenced by the existence of proglacial lakes, which are worldwide increasing in number and size. We examine the recent changes of the terminus of Pasterze Glacier by discussing the thinning and dynamics of the glacier terminus along with the changes of the glacial-proglacial transition zone between September 2016 and September 2021. By considering land cover in the interpretation, we find that glacier surface characteristics show different rates of elevation changes and surface movement. We mainly use orthophotos and digital elevation models (DEMs) resulting from airborne surveys of 12 different acquisition dates, but also draw on ablation stake measurements, lake water level data, water temperature data, as well as thermal infrared (TIR) imagery. While debris-covered ice lowered typically −5.0 m a−1 ± 4.6 m a−1 (mean ± standard deviation), debris-free ice was affected by ablation in the range of −7.0 m a−1 ± 2.7 m a−1, thus demonstrating that melt rates in similar elevations are related to surface characteristics. The elevation change rates were, in most cases, in a similar range throughout the observed periods of time. The horizontal displacement close to glacier-marginal crevasses amounted to up to ∼8 m a−1, but was mostly in the range of ∼1–4 m a−1. Considering both horizontal displacement and elevation changes, we find that clean and dirty ice surfaces show larger thickness losses and are moving faster compared to debris-covered glacier surfaces. Diurnal and seasonal fluctuations of lake water levels in the range of decimeters and lake water temperatures mostly clearly exceeding 0 °C are indicative of the potential influence of the proglacial lake on the glacier terminus. Given the decelerating and decaying behavior of the Pasterze Glacier in recent decades, we interpret the change rates of surface lowering and horizontal displacement 2016–2021 to be influenced by other factors such as the recently formed proglacial lake. This is also supported by direct ablation measurements that mostly show lesser ice melt differences compared to DEM-based surface elevation changes, suggesting that other factors such as thermally-induced melting contributed to an increased elevation difference.

Polarization sensitive electronically tuned microgroove array THz active modulator

The 6G technology has identified the frequency range of 0.1 to 1 THz as the communication band, with a particular focus on ultrafast modulation and multi-dimensional resolution coding technology. To advance the applications of THz photonics, there is a critical need for high-performance active optoelectronic THz devices. One potential solution involves the utilization of electrically controlled semi-metallic based THz modulators, which can provide suitable modulation depth and a wide modulation bandwidth. In this research, a semi-metallic TiS2 nanofilm device was developed using femtosecond laser direct ablation. The combination of structural effects and TiS2 absorption has significantly improved active modulation. These findings indicate that TiS2-based devices are well-suited for applications in THz photonics.

Design of "green" plasmonic nanocomposites with multi-band blue emission for ultrafast laser hyperthermia.

Although non-toxic nanoscale materials are widely employed for different healthcare applications, their performance is still considerably limited. In this paper, various approaches using the environmentally friendly ultrafast laser processing were employed to remodel IV group semiconductor nanostructures and synthesize highly-stable (ξ-potential is up to -47 mV) colloidal solutions of plasmonic (525 nm) nanocomposites with a strong size-dependent chemical content. All nanocomposites exhibited a remarkable lamp-excited multi-band blue emission centred at around 420 nm that is considerably (∼10-fold for Au-SiC) stronger than from nanocomposites prepared by the laser co-fragmentation technique. The latter formed a greater quantity of smaller narrowly dispersed (∼4 nm for Au-Si) plasmonic nanostructures compared to the direct laser ablation method. Moreover, it led to a greater number of semiconductor elements (∼1.7-fold for Au-Ge) in the nanocomposites, which was correlated with lower (∼30%) electrical conductivity. Aqueous colloidal solutions revealed a greater degree (∼80%) of the femtosecond laser-induced heating for all nanocomposites formed by direct laser ablation. These findings highlight the peculiarities of the applied laser processing approaches and considerably facilitate the design of specific multi-modal plasmonic-fluorescence (biosensing, bioimaging, hyperthermia) nanocomposites with a required performance that significantly expands the application area of semiconductor nanostructures.

Surgical ablation of long-standing persistent atrial fibrillation: 1-year outcomes from the CArdioSurgEry Atrial Fibrillation (CASE-AF) registry.

The CArdioSurgEry Atrial Fibrillation (CASE-AF) registry is a prospective, multicentre study for collecting and analysing real-world data of surgical atrial fibrillation (AF) treatment. This study aimed to evaluate outcomes of surgery for long-standing persistent AF at 1 year. In total, 17 centres consecutively include all eligible patients with continuous AF lasting for ≥1 year. Exclusion criteria are missing informed consent or age <18 years. For patient-reported outcomes measures, the European Heart Rhythm Association score was used. No presence of AF (based on ECG findings including Holter ECG and/or implanted devices), no re-ablation, no further cardioversion and no rehospitalization due to AF after a 3-month blanking period defined no AF recurrence at 1 year. From January 2017 to January 2020, a total of 1115 patients were enrolled in CASE-AF. Of them, 202 patients (mean age 69.7 ± 7.8 years, 27.2% female) underwent surgical ablation of long-standing persistent AF (study cohort), mostly accompanied by left atrial appendage closure (n = 180 [89%], resection n = 75 [42%]) and predominantly performed as concomitant (n = 174 [86%]) and left atrial only procedure (n = 144 [71%]). Early mortality (30 days) was 2.0% and morbidity was low. At follow-up (median 14.4 months, interquartile range, 12.7-17.6 months, 100% complete), 106 patients (56%) had no AF recurrence and 93% of them were asymptomatic. AF recurrence was accompanied by AF-related rehospitalization (n = 12, P = 0.003), direct current shock cardioversion (n = 23, P < 0.001), AF ablation (n = 7, P = 0.003) and stroke (n = 3, P = 0.059). Multivariable analysis identified cryoablation, predominantly performed endocardially including additional left atrial (74%) and biatrial (42%) lesions, as a significant factor for freedom from AF recurrence (odds ratio 2.7, 95% confidence interval 1.07-6.79, P = 0.035). According to CASE-AF, surgical ablation of long-standing persistent AF is most effective when concomitantly performed using endocardial cryoablation. Ongoing follow-up allows further elucidation of efficacious treatment strategies.

High-quality and efficient large-area copper removal utilizing laser-induced active mechanical peeling

Large-area copper layer removal is one of the essential processes in manufacturing printed circuit boards (PCB) and frequency selective surfaces (FSS). However, laser direct ablation (LDA) with one-step scanning is challenging in resolving excessive substrate damage and material residue. Here, this study proposes a laser scanning strategy based on the laser-induced active mechanical peeling (LIAMP) effect generated by resin decomposition. This scanning strategy allows the removal of large-area copper layers from FR-4 copper-clad laminates (FR-4 CCL) in one-step scanning without additional manual intervention. During the removal process, the resin decomposition in the laser-irradiated area provides the mechanical tearing force, while the resin decomposition in the laser-unirradiated area reduces the interfacial adhesion force and provides recoil pressure. By optimizing scanning parameters to control the laser energy deposition, the substrate damage and copper residue can be effectively avoided. In our work, the maximum removal efficiency with different energy densities, pulse duration, and repetition frequency are 31.8 mm2/ms, 30.25 mm2/ms, and 82.8 mm2/ms, respectively. Compared with the reported copper removal using laser direct write lithography technology combined with wet chemical etching (LDWL+WCE) and LDA, the efficiency improved by 8.3 times and 66 times. Predictably, the laser scanning strategy and the peeling mechanism are simple and controllable, which have potential in electronics, communications, and aerospace.