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Minimum energy configurations in 2D material-based heterostructures can enable interactions with external chemical species that are not observable for their monolithic counterparts. Density functional theory (DFT) calculations reveal that the binding energy of divalent toxic metal ions of Cd, Pb, and Hg on graphene-gold heterointerfaces is negative, in contrast to the positive value associated with free-standing graphene. The theoretical predictions are confirmed experimentally by Surface Plasmon Resonance (SPR) spectroscopy, where a strong binding affinity is measured for all the heavy metal ions in water. The results indicate the formation of a film of heavy metal ions on the graphene-gold (Gr/Au) heterointerfaces, where the adsorption of the ions follows a Langmuir isotherm model. The highest thermodynamic affinity constant K = 3.1 × 107 L mol-1 is observed for Hg2+@Gr/Au heterostructures, compared to 1.1 × 107 L mol-1 and 8.5 × 106 L mol-1 for Pb2+@Gr/Au and Cd2+@Gr/Au, respectively. In the case of Hg2+ ions, it was observed a sensitivity of about 0.01°/ppb and a detection limit of 0.7 ppb (∼3 nmol L-1). The combined X-ray photoelectron spectroscopy (XPS) and SPR analysis suggests a permanent interaction of all of the HMIs with the Gr/Au heterointerfaces. The correlation between the theoretical and experimental results indicates that the electron transfer from the graphene-gold heterostructures to the heavy metal ions is the key for correct interpretation of the enhanced sensitivity of the SPR sensors in water.

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Understanding the interfacial electronic structures of organic semiconductor phthalocyanines (MePc) and graphene is essential for their practical application in various fields. In this study, we investigated the electronic structure and the tuning of the work function of free metal phthalocyanine (Pc4), cobalt phthalocyanine (CoPc), and copper phthalocyanine (CuPc) molecules deposited on a graphene monolayer using X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). We found that the functionalization of MePc molecules induces p-doping to the graphene substrate due to the charge transfer mechanism with the MePc molecule. XPS analysis shows that the electronic interaction at the interface between Pc molecules and graphene substrate mainly occurs through the pyrrole species. Comparatively, it was observed that the electronic coupling between graphene and CuPc is relatively stronger than that between CoPc and graphene. The electronic interaction of the CuPc/Gr sample principally occurs through the Cu2+ 3d states of CuPc, the molecule, and the graphene 2p π states. This electronic interaction increases the work function of the graphene substrate to 5.75 eV, 6.05 eV, and 6.12 eV after depositing the Pc4, CoPc, and CuPc molecules, respectively. These results show that the MePc/Gr samples investigated in this study can be considered promising candidates for applications requiring a high work function to increase hole injection efficiency.

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Resumen El uso de dispositivos cardiacos implantables ha aumentado en los últimos años, lo que ha generado un aumento en el número de procedimientos de extracción de electrodos a medida que se intervienen pacientes con un mayor número de comorbilidades. En la actualidad, la técnica percutánea de extracción es de elección en la mayoría de los pacientes debido a los excelentes resultados alcanzados y a una morbi-mortalidad asociada inferior a la de la extracción quirúrgica. No obstante, algunos pacientes pueden presentar retos que aumentan el grado de dificultad técnica del procedimiento, entre los que se encuentran variantes anatómicas, calcificaciones extensas o la necesidad de extraer electrodos de fijación pasiva. Se expone el caso de la extracción de un electrodo disfuncionante en una paciente portadora de marcapasos por bloqueo auriculoventricular completo, con estimulación diafragmática por electrodo ventricular de fijación pasiva implantado a través de una vena cava superior izquierda persistente en una vena posterolateral del seno coronario.

Abstract The use of cardiac electronic devices has increased over the last decades, which has generated an increase in the number of electrode extraction procedures, as a greater number of patients with multiple comorbidities undergo cardiac electronic device implantation. Currently, the percutaneous technique is preferable in most patients, given its excellent clinical results and lower morbidity and mortality compared to surgical extraction. Nonetheless, some clinical scenarios increase procedural difficulty, including anatomical variants, or the need to extract passive fixation leads. We present a case of a patient with pacemaker due to complete atrioventricular block, with diaphragmatic stimulation caused by a passive fixation ventricular electrode that was implanted in a posterolateral vein of the coronary sinus through a persistent left superior vena cava, who underwent successful transvenous lead extraction.

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Three F2-derived biparental doubled haploid (DH) maize populations were generated for genetic mapping of resistance to common rust. Each of the three populations has the same susceptible parent, but a different resistance donor parent. Population 1 and 3 consist of 320 lines each, population 2 consists of 260 lines. The DH lines were evaluated for their susceptibility to common rust in two years and with two replications in each year. For phenotyping, a visual score (VS) for susceptibility was assigned. Additionally, unmanned aerial vehicle (UAV) derived multispectral and thermal infrared data was recorded and combined in different vegetation indices ("remote sensing", RS). The DH lines were genotyped with the DarTseq method, to obtain data on single nucleotide polymorphisms (SNPs). After quality control, 9051 markers remained. Missing values were "imputed" by the empirical mean of the marker scores of the respective locus. We used the data for comparison of genome-wide association studies and genomic prediction when based on different phenotyping methods, that is either VS or RS data. The data may be interesting for reuse for instance for benchmarking genomic prediction models, for phytopathological studies addressing common rust, or for specifications of vegetation indices.

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Breeding for disease resistance is a central component of strategies implemented to mitigate biotic stress impacts on crop yield. Conventionally, genotypes of a plant population are evaluated through a labor-intensive process of assigning visual scores (VS) of susceptibility (or resistance) by specifically trained staff, which limits manageable volumes and repeatability of evaluation trials. Remote sensing (RS) tools have the potential to streamline phenotyping processes and to deliver more standardized results at higher through-put. Here, we use a two-year evaluation trial of three newly developed biparental populations of maize doubled haploid lines (DH) to compare the results of genomic analyses of resistance to common rust (CR) when phenotyping is either based on conventional VS or on RS-derived (vegetation) indices. As a general observation, for each population × year combination, the broad sense heritability of VS was greater than or very close to the maximum heritability across all RS indices. Moreover, results of linkage mapping as well as of genomic prediction (GP), suggest that VS data was of a higher quality, indicated by higher -logp values in the linkage studies and higher predictive abilities for genomic prediction. Nevertheless, despite the qualitative differences between the phenotyping methods, each successfully identified the same genomic region on chromosome 10 as being associated with disease resistance. This region is likely related to the known CR resistance locus Rp1. Our results indicate that RS technology can be used to streamline genetic evaluation processes for foliar disease resistance in maize. In particular, RS can potentially reduce costs of phenotypic evaluations and increase trialing capacities.

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BACKGROUND: Intracardiac echocardiography (ICE) is increasingly used during left atrial appendage occlusion (LAAO) as an alternative to transesophageal echocardiography (TEE). The objective of this study is to evaluate the impact of ICE versus TEE guidance during LAAO on procedural characteristics and acute outcomes, as well the presence of peri-device leaks and residual septal defects during follow-up. METHODS: All studies comparing ICE-guided versus TEE-guided LAAO were identified. The primary outcomes were procedural efficacy and occurrence of procedure-related complications. Secondary outcomes included lab efficiency (defined as a reduction in in-room time), procedural time, fluoroscopy time, and presence of peri-device leaks and residual interatrial septal defects (IASD) during follow-up. RESULTS: Twelve studies (n = 5637) were included. There were no differences in procedural success (98.3% vs. 97.8%; OR 0.73, 95% CI 0.42-1.27, p = .27; I2 = 0%) or adverse events (4.5% vs. 4.4%; OR 0.81 95% CI 0.56-1.16, p = .25; I2 = 0%) between the ICE-guided and TEE-guided groups. ICE guidance reduced in in-room time (mean-weighted 28.6-min reduction in in-room time) without differences in procedural time or fluoroscopy time. There were no differences in peri-device leak (OR 0.93, 95% CI 0.68-1.27, p = 0.64); however, an increased prevalence of residual IASD was observed with ICE-guided versus TEE-guided LAAO (46.3% vs. 34.2%; OR 2.23, 95% CI 1.05-4.75, p = 0.04). CONCLUSION: ICE guidance is associated with similar procedural efficacy and safety, but could result in improved lab efficiency (as established by a significant reduction in in-room time). No differences in the rate of periprocedural leaks were found. A higher prevalence of residual interatrial septal defects was observed with ICE guidance.

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Resumen Introducida inicialmente en la década de los cincuenta para la evaluación de las presiones de la aurícula izquierda y posteriormente para la realización de valvuloplastia mitral, la punción transeptal es, con frecuencia, la vía de acceso para efectuar procedimientos que involucren las cavidades izquierdas. En la actualidad, se usa comúnmente en los laboratorios de electrofisiología, tanto para la ablación de arritmias en cavidades izquierdas como para los procedimientos de cierre percutáneo de orejuela. No obstante, con la llegada de diversas técnicas para el manejo percutáneo de la válvula mitral, se espera un aumento progresivo de su uso por parte de cardiólogos intervencionistas. En este artículo, se revisa la técnica para hacer una punción transeptal segura y se dan recomendaciones y estrategias para el manejo de la punción transeptal difícil.

Abstract Initially described in 1959 as a technique to measure left atrial pressures, and later used during balloon mitral valvuloplasty, transeptal puncture (TSP) is frequently the access route for procedures involving the left heart chambers. Currently, it is mostly used in electrophysiology laboratories for arrhythmia ablation and during left atrial appendage occlusion procedures. However, with the ongoing development of percutaneous mitral valve interventions, it is expected that a greater number of interventional cardiologists will be using this technique in the near future. In this article, we review the technique to perform TSP safely, and we provide recommendations and different strategies to deal with difficult TSPs.

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BACKGROUND: Endoscopic sleeve gastroplasty (ESG) is a minimally invasive procedure used in the treatment of obesity, with a complication rate of less than 2% of cases. There have been only two reported cases worldwide of gallbladder injuries as a major complication of ESG. CASE SUMMARY: We present the case of a 34-year-old patient who developed a complication after ESG. The patient experienced epigastric and right hypochondrium pain 12 h after the procedure, and a positive Murphy's sign was identified on physical examination. Laboratory results showed a leukocyte count of 17 × 103/µL, and computed tomography indicated the presence of free fluid in the pelvic cavity and perihepatic recesses as well as a possible suture in the wall of the Hartmann's pouch toward the anterior surface of the stomach. A diagnostic laparoscopy was performed, revealing plication of the Hartmann's pouch wall to the anterior stomach wall. Laparoscopic cholecystectomy and lavage were carried out. The patient had a stable recovery and was discharged 72 h after surgery, tolerating oral intake. CONCLUSION: Gallbladder plication should be suspected if signs and symptoms consistent with acute cholecystitis occur after ESG.

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Resumen El cierre percutáneo de orejuela se ha posicionado como una estrategia eficaz en la prevención de embolia en pacientes con fibrilación auricular. La mayoría de los procedimientos en el mundo se realizan mediante ecocardiografía transesofágica, que implica, en la mayoría de los casos, el uso de sedación profunda guiada por anestesiología o incluso anestesia general, lo que conlleva tiempos de sala y de procedimiento prolongados, potenciales retardos en la programación del procedimiento (por baja disponibilidad de servicios de anestesiología y de ecocardiografía) y exposición a los riesgos propios de la sedación profunda y la anestesia general. Adicionalmente, el mayor número de personas requeridos en sala para el cierre percutáneo de orejuela guiado por ecacardiografía transesofágica aumenta la cantidad de personas expuestas a radiación ionizante, particularmente el ecocardiografista, que se ubica próximo al angiógrafo y con frecuencia debe introducir sus manos en el campo de fluoroscopia. En los últimos años, la ecocardiografía intracardíaca ha cobrado importancia para guiar los procedimientos de cierre percutáneo de orejuela debido a su amplia disponibilidad en los laboratorios de electrofisiología, y a la posibilidad de realizar procedimientos con menor tiempo de uso de sala y de recuperación, ya que evita el uso de anestesia general y a que facilita los procedimientos con alta el mismo día, lo que se podría asociar a una disminución global de los costos de procedimientos. En este artículo se discute la evidencia actual que avala el uso de ecocardiografía intracardiaca en el cierre percutáneo de orejuela.

Abstract Left atrial appendage occlusion has proven to be an effective strategy in reducing the risk of stroke and systemic embolism in patients with atrial fibrillation. Worldwide, most left atrial appendage occlusions are performed using transesophageal echocardiography, which requires the use of monitored anesthesia care or general anesthesia, resulting in prolonged in-room and procedural times, delays in procedural scheduling (due to a low availability of anesthetic and echocardiography services) and the risks associated with anesthesia per se. Moreover, the additional personnel required to perform left atrial appendage occlusion guided by transesophageal echocardiography increases the number of people exposed to ionizing radiation, which is particularly high for the transesophageal echocardiography operator, who stands beside the fluoroscopy tube and frequently introduces his/her hands in the fluoroscopy field. Intracardiac echocardiography has gained acceptance to guide left atrial appendage occlusion in recent years, given its high availability in electrophysiology labs, as well as its potential to reduce in-room and procedural times, reduce the need for extensive recovery times, avoid the use of general anesthesia and facilitating same-day discharge, all of which could result in a reduction of total procedure-related costs. In this article, we discuss the evidence supporting the use of intracardiac echocardiography guidance during left atrial appendage occlusion.

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We investigated the interfacial electronic structure of the bidimensional interface of single-layer graphene on a germanium substrate. The procedure followed a well-established approach using ultraviolet (UPS) and X-ray (XPS) photoelectron spectroscopy. The direct synthesis of the single-layer graphene on the surface of (110) undoped Ge substrates was conducted via chemical vapor deposition (CVD). The main graphitic properties of the systems were identified, and it was shown that the Ge substrate affected the electronic structure of the single-layer graphene, indicating the electronic coupling between the graphene and the Ge substrate. Furthermore, the relevant features associated with the Schottky contact's nature, the energy level's alignments, and the energy barrier's heights for electron and hole injection were obtained in this work. The results are useful, given the possible integration of single-layer graphene on a Ge substrate with the complementary metal-oxide-semiconductor (CMOS) technology.

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Biological nitrification inhibition (BNI) is a plant function where root systems release antibiotic compounds (BNIs) specifically aimed at suppressing nitrifiers to limit soil-nitrate formation in the root zone. Little is known about BNI-activity in maize (Zea mays L.), the most important food, feed, and energy crop. Two categories of BNIs are released from maize roots; hydrophobic and hydrophilic BNIs, that determine BNI-capacity in root systems. Zeanone is a recently discovered hydrophobic compound with BNI-activity, released from maize roots. The objectives of this study were to understand/quantify the relationship between zeanone activity and hydrophobic BNI-capacity. We assessed genetic variability among 250 CIMMYT maize lines (CMLs) characterized for hydrophobic BNI-capacity and zeanone activity, towards developing genetic markers linked to this trait in maize. CMLs with high BNI-capacity and ability to release zeanone from roots were identified. GWAS was performed using 27,085 SNPs (with unique positions on the B73v.4 reference genome, and false discovery rate = 10), and phenotypic information for BNI-capacity and zeanone production from root systems. Eighteen significant markers were identified; three associated with specific BNI-activity (SBNI), four with BNI-activity per plant (BNIPP), another ten were common between SBNI and BNIPP, and one with zeanone release. Further, 30 annotated genes were associated with the significant SNPs; most of these genes are involved in pathways of "biological process", and one (AMT5) in ammonium regulation in maize roots. Although the inbred lines in this study were not developed for BNI-traits, the identification of markers associated with BNI-capacity suggests the possibility of using these genomic tools in marker-assisted selection to improve hydrophobic BNI-capacity in maize.

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BACKGROUND: Fluid replacement during exercise has been studied as an important strategy to enhance recovery, however, studies are needed to investigate the effect of this strategy in different physical profiles. The aim of the study was to investigate the influence of physical fitness of coronary artery disease (CAD) patients on vagal reentry and heart rate recovery after exercise performed with and without fluid replacement. METHODS: Nonrandomized crossover clinical trial. Thirty-three CAD patients were submitted to (I) cardiopulmonary exercise test: to divide the sample into lower and higher VO2  peak groups; (II) control protocol (CP): composed of rest, aerobic exercise and passive recovery; (III) hydration protocol (HP): composed of the same activities as the CP, but with water intake during exercise. The recovery was evaluated by vagal reentry and heart rate recovery immediately after exercise. RESULTS: The results did not show significant differences between the higher and lower VO2  peak groups. In addition, the hydration strategy adopted was not able to cause significant changes between control and HPs, regardless of group. However, a time effect was observed, suggesting anticipation of vagal reactivation and heart rate reduction in HP. CONCLUSIONS: Physical fitness did not influence vagal reentry and heart rate recovery in CAD patients after exercise. However, the hydration strategy seems to have anticipated vagal reentry and produced a more efficient reduction in heart rate regardless of the individuals' physical fitness, but these results should be analyzed with caution due to the absence of significant differences between groups and protocols.

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ABSTRACT: Breast cancer in men is a rare and unsuspected malignancy. A 48-year-old man begins with disabling low back pain. The CT scan reported a compression fracture in L2 and diffuse skeletal lesions suggestive of metastatic disease. The serum prostate-specific antigen was 6.2 ng/mL. He was referred for SPECT/CT with 99m Tc-EDDA/HYNIC-inhibitor prostate-specific membrane antigen due to clinical suspicion of prostate cancer. SPECT/CT with 99m Tc-EDDA/HYNIC-inhibitor prostate-specific membrane antigen showed a primary lesion in the left breast and multiple bone lesions. Biopsy confirmed infiltrating ductal carcinoma with positive hormone receptors and indeterminate HER2 (human epidermal growth factor receptor 2).

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This study aimed to describe the epidemiological indexes of mastitis, milk quality and udder hygiene in the Compost Barn system, as well as to search for associations between isolated pathogens from milk with compost characteristics. Three dairy herds participated in the study, and the samples were collected during different periods on each farm. Individual milk samples were collected in duplicate for SCC analysis and microbiological culture. Environmental pathogens caused most cases of clinical mastitis on farm 2, and contagious pathogens caused the most cases on farm 1. Bed moisture was not associated with the incidence of environmental pathogens. Most of the animals remained in good udder hygiene during the study. Poor udder hygiene contributed to the increased incidence of environmental pathogens in one of the farms. A higher number of animals with a hygiene score of ≥ 2 were observed during the warmer and rainfall periods. There was no association between hygiene scores and somatic cell counts. The results suggest that pathogens isolated from milk in animals confined in Compost Barn under tropical climate are like other confinement systems adopted elsewhere. The year period influenced the udder hygiene score, reinforcing the importance of bed management throughout the year.

O objetivo deste estudo foi descrever os índices epidemiológicos da mastite, da qualidade do leite e da higiene do úbere em animais confinados no sistema Compost Barn, bem como buscar associações entre patógenos isolados do leite e características do composto. Três rebanhos leiteiros participaram do estudo e as amostras foram coletadas em diferentes períodos em cada fazenda. Amostras individuais de leite foram coletadas em duplicata para análise de CCS e cultura microbiológica. Patógenos ambientais causaram a maioria dos casos de mastite clínica na fazenda 2, e na fazenda 1 a maioria dos casos foi em decorrência de patógenos contagiosos. Amostras de material da cama foram coletadas em duas fazendas para análise da densidade bacteriana e da umidade. A umidade da cama permaneceu dentro da faixa de controle durante o estudo e não foi associada à incidência de patógenos ambientais. A maioria dos animais permaneceu com boa higiene de úbere durante o estudo. A falta de higiene do úbere contribuiu para o aumento da incidência de patógenos ambientais em uma das fazendas. Durante o período mais quente e mais chuvoso, um número maior de animais com escore de sujidade ≥2 foi observado em todos os rebanhos. Não houve associação entre escore de sujidade e contagem de células somáticas em qualquer uma das três fazendas. Os resultados indicam que o perfil de patógenos isolados do leite em animais confinados em Compost Barn sob clima tropical é semelhante a outros sistemas de confinamento adotados em outros lugares. O período do ano influenciou o escore de higiene do úbere, o que reforça a importância do manejo da cama ao longo do ano.

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New data of creep and viscoelastic Poisson's ratio, ν(t), of five engineering elastomers (Ethylene Propylene-Diene Monomer, Flouroelastomer (Viton®), nitrile butadiene rubber, silicone rubber and neoprene/chloroprene rubber) at different stress (200, 400 and 600 kPa) and temperature (25, 50 and 80 °C) are presented. The ν(t) was characterized through an experimental methodological approach based on creep testing (30 min) and strain (axial and transverse) measurements by digital image correlation. Initially, creep behavior in axial and transverse directions was characterized for each elastomer and condition, and then each creep curve was fitted to a four-element creep model to obtain the corresponding functions. The obtained functions were used to estimate ν(t) for prolonged times (300 h) through a convolution equation. Overall, the characterization was achieved for the five elastomers results exhibiting ν(t) increasing with temperature and time from about 0.3 (for short-term loading) to reach and stabilize at about 0.48 (for long-term loading).

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Resumen La fibrilación auricular es la arritmia más prevalente en la práctica clínica, y se asocia con una morbimortalidad significativa, la cual, en parte, se explica por el riesgo de fenómenos embólicos. En la actualidad, el uso de anticoagulantes es el estándar de manejo en aquellos pacientes con riesgo embólico significativo (dado por un puntaje ≥ 2 en la escala CHA2DS2Vasc). Sin embargo, algunos pacientes tienen contraindicaciones que impiden recibir este tipo de tratamiento a largo plazo, en cuyo caso se considera el cierre percutáneo de la orejuela como medida para la disminución del riesgo de embolia. Al requerir una punción transeptal, la presencia de dispositivos de cierre de defectos del septo interauricular dificulta el procedimiento de manera significativa. Se presenta el caso de una paciente con contraindicación absoluta para recibir anticoagulantes debido a sangrado gastrointestinal y antecedente de cierre percutáneo de comunicación interauricular sometida a cierre percutáneo de orejuela como alternativa terapéutica a la anticoagulación.

Abstract Atrial fibrillation is the most prevalent arrythmia in clinical practice, associated with a significant morbimortality explained, in part, by the high risk of embolic phenomena. The use of anticoagulation is the standard of care in those patients with increased embolic risk (given by a score ≥ 2 in the CHA2DS2Vasc scale). However, some patients have contraindications to receiving this treatment long-term, in which case percutaneous left atrial appendage occlusion can be considered as a means of decreasing their embolic risk. Because the procedure requires transeptal puncture, the presence of devices for atrial septal defect closure can difficult the technique. We present the case of a patient with absolute contraindication to anticoagulation therapy given gastrointestinal bleeding, with history of percutaneous closure of interauricular communication, who was treated with percutaneous left atrial appendage occlusion as an alternative to oral anticoagulants.

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Approximately 70% of the patients with systemic lupus erythematosus will have clinical evidence of kidney damage during their evolution. Patients with impaired renal function at onset and those with recurrent flares have a poor prognosis. Understanding the mechanism of action of immunosuppressants is essential for proper prescription. Steroids inhibit the DNA sequence that promotes the release of inflammatory cytokines. Phosphoramide mustard, metabolite of cyclophosphamide, cross-link with the DNA, causing the aggregation of an alkyl group, causing cell death. Mycophenolate inhibits inosine monophosphate dehydrogenase, prevents de novo synthesis of guanine, inducing cell arrest in S phase. Azathioprine blocks the synthesis of purines and induces apoptosis. Calcineurin inhibitors prevent the dephosphorylation of NFAT and reduce the production of interleukin 2. Antimalarials alter the enzymatic release of lysosomes by increasing intravesicular pH. The mechanism of action of rituximab is related to complement-dependent cytotoxicity and the elimination of anti-CD20-labeled B cells. Progress in the knowledge and management of low doses of steroids may change the current paradigm and reduce the frequency of related adverse events. Mycophenolate seems to be a better choice than cyclophosphamide for induction, it is also preferred over azathioprine as a maintenance immunosuppressive agent, although azathioprine is preferred in women with a desire for conception, those pregnant, or with low resources. For treatment-resistant cases, tacrolimus, rituximab or belimumab may be effective. Ongoing clinical trials with new drugs offer promising results.

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Organic/inorganic van der Waals heterojunctions formed by a combination of 2D materials with semiconductor polymer films enable the fabrication of new device architectures that are interesting for electronic and optoelectronic applications. Here, we investigated the charge-transfer dynamics at the interface between 2D layered franckeite (Fr) and two thiophene-based conjugated polymers (PFO-DBT and P3HT) from the resonantly core-excited electron. The unoccupied electronic states of PFO-DBT/Fr and P3HT/Fr heterojunctions were studied using near-edge X-ray absorption fine structure (NEXAFS) and resonant Auger (RAS) synchrotron-based spectroscopies. We found evidence of ultrafast (subfemtosecond charge-transfer times) interfacial electron delocalization pathways from specific electronic states. For the interface between the PFO-DBT polymer and exfoliated franckeite, the most efficient interfacial electron delocalization pathways were found through π*(S-N) and π*(S-C) electronic states corresponding to the benzothiadiazole and thiophene units. On the other hand, for the P3HT polymer, we found that electrons excited to π-π* and S1s-π*(C-C) electronic states of the P3HT polymer are the most affected by the presence of exfoliated franckeite and consequently are the main interfacial electron-transfer pathways in this heterojunction. Our results have important implications in understanding how ultrafast electron delocalization is taking place in organic/inorganic van der Waals heterojunctions, which is relevant information in designing new devices involving these systems.

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BACKGROUND: Transvenous lead extraction (TLE) is standard of care for the management of patients with cardiac implantable electronic device infection or lead-related complications. Currently, objective data on TLE in Latin America is lacking. OBJECTIVE: To describe the current practice standards in Latin American centers performing TLE. METHODS: An online survey was sent through the mailing list of the Latin American Heart Rhythm Society. Online reminders were sent through the mailing list; duplicate answers were discarded. The survey was available for 1 month, after which no more answers were accepted. RESULTS: A total of 48 answers were received, from 44 different institutions (39.6% from Colombia, 27.1% from Brazil), with most respondents (82%) being electrophysiologists. Twenty-nine institutions (66%) performed <10 lead extractions/year, with 7 (16%) institutions not performing lead extraction. Although most institutions in which lead extraction is performed reported using several tools, mechanical rotating sheaths were cited as the main tool (66%) and only 13% reported the use of laser sheaths. Management of infected leads was performed according to current guidelines. CONCLUSION: This survey is the first attempt to provide information on TLE procedures in Latin America and could provide useful information for future prospective registries. According to our results, the number of centers performing high volume lead extraction in Latin America is smaller than that reported in other continents, with most interventions performed using mechanical tools. Future prospective registries assessing acute and long-term success are needed.

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