Multi-Variable Multi-Metric Optimization of Self-Assembled Photocatalytic CO2 Reduction Performance Using Machine Learning Algorithms.

The sunlight-driven reduction of CO2 into fuels and platform chemicals is a promising approach to enable a circular economy. However, established optimization approaches are poorly suited to multivariable multimetric photocatalytic systems because they aim to optimize one performance metric while sacrificing the others and thereby limit overall system performance. Herein, we address this multimetric challenge by defining a metric for holistic system performance that takes multiple figures of merit into account, and employ a machine learning algorithm to efficiently guide our experiments through the large parameter matrix to make holistic optimization accessible for human experimentalists. As a test platform, we employ a five-component system that self-assembles into photocatalytic micelles for CO2-to-CO reduction, which we experimentally optimized to simultaneously improve yield, quantum yield, turnover number, and frequency while maintaining high selectivity. Leveraging the data set with machine learning algorithms allows quantification of each parameter's effect on overall system performance. The buffer concentration is unexpectedly revealed as the dominating parameter for optimal photocatalytic activity, and is nearly four times more important than the catalyst concentration. The expanded use and standardization of this methodology to define and optimize holistic performance will accelerate progress in different areas of catalysis by providing unprecedented insights into performance bottlenecks, enhancing comparability, and taking results beyond comparison of subjective figures of merit.

Realizing Symmetry-Breaking Architectures in Soap Films.

We show here that soap films-typically expected to host symmetric molecular arrangements-can be constructed with differing opposite surfaces, breaking their symmetry, and making them reminiscent of functional biological motifs found in nature. Using fluorescent molecular probes as dopants on different sides of the film, resonance energy transfer could be employed to confirm the lack of symmetry, which was found to persist on timescales of several minutes. Further, a theoretical analysis of the main transport phenomena involved yielded good agreement with the experimental observations.

Ultrasound-guided Axillary Vein Puncture for Cardiac Device Implantation: A Safe and Effective Approach.

Ultrasound-guided axillary vein access is an effective alternative to conventional subclavian and cephalic access for cardiac implantable electronic device implantation. The aim of this study was to compare the safety, efficacy, and radiation exposure data of the ultrasound-guided axillary approach with other conventional access techniques. The study population included 130 consecutive patients, stratified as 65 (64% male; median age, 79 years) in the study group and 65 (66% male; median age, 81 years) in the control group. We performed a retrospective not-randomized analysis by comparing ultrasound-guided axillary vein puncture with subclavian and cephalic approaches in order to test the effect on X-ray exposure, total procedure time, and complications. Significant differences were observed in terms of radiation exposure, including fluoroscopy time (median, 95 s [study group] vs. 193 s [control group]; P < .001), air kerma (median, 29 mGy [study group] vs. 55.7 mGy [control group]; P < .001), and dose-area product (median, 8219 mGy·cm2 [study group] vs. 16736 mGy·cm2 [control group]; P < .001). The median procedure time was 45 min in the study group but 50 min in the control group (P < .05). Complications occurred in 6 control group patients (1 urticaria contrast medium-related, 3 pneumothorax, 2 subclavian artery puncture) and 2 study group patients (2 axillary artery puncture). We conclude that the ultrasound-guided axillary venous approach is a fast, feasible, and safe technique for cardiac lead implantation. It allows a significant reduction in fluoroscopy time without prolonging the procedural time. This approach offers direct visualization of the vessel during the puncture, so it can be useful in patients who cannot receive contrast medium, those who require "difficult" thoracic approaches (emphysema, too much or too little fat tissue), or those on anticoagulant therapy.

A novel concept of photosynthetic soft membranes: a numerical study.

We focus on a novel concept of photosynthetic soft membranes, possibly able to allow the conversion of solar energy and carbon dioxide (CO[Formula: see text]) into green fuels. The considered membranes rely on self-assembled functional molecules in the form of soap films. We elaborate a multi-scale and multi-physics model to describe the relevant phenomena, investigating the expected performance of a single soft photosynthetic membrane. First, we present a macroscale continuum model, which accounts for the transport of gaseous and ionic species within the soap film, the chemical equilibria and the two involved photocatalytic half reactions of the CO[Formula: see text] reduction and water oxidation at the two gas-surfactant-water interfaces of the soap film. Second, we introduce a mesoscale discrete Monte Carlo model, to deepen the investigation of the structure of the functional monolayers. Finally, the morphological information obtained at the mesoscale is integrated into the continuum model in a multi-scale framework. The developed tools are then used to perform sensitivity studies in a wide range of possible experimental conditions, to provide scenarios on fuel production by such a novel approach.

An atypical pacemaker pocket hematoma containing chyliform fluid.

Subcutaneous hematoma is a complication of cardiac device implantation. In most cases, it is drained or spontaneously reabsorbed. While cases of chylothorax are rare, and cases of pseudochylothorax even rarer, previous cases of accumulation of chyliform material in the subcutaneous pockets of cardiac devices are anecdotal. We present a case of a 60-year-old man with antiphospholipids antibody syndrome and rheumatoid arthritis, who underwent dual-chamber ICD implantation in December 2020; the procedure was complicated by a pocket hematoma, which required surgical drainage. After 7 months, the man returned owing to heart failure, with evidence of the reappearance of a large swelling in the ICD pocket; this was tolerated for months by the patient and was no longer controlled. We drained 100ml of gold-colored, odorless liquid, and found no evidence of blood material in the pocket. The liquid was not pus, as culture testing proved negative for bacterial growth. Chemical-physical examination revealed elevated cholesterol concentration (704 mg/dl) and low levels of triglycerides (80 mg/dl; plasma cholesterol values were 91mg/dl, and triglycerides 48 mg/dl). Microscopic examination revealed isolated leukocytes and rare erythrocytes immersed in mucoid material; cytological analysis showed a carpet of macrophages filled with cholesterol. This evidence supports the diagnosis of pseudochyle fluid, formed by the degradation of a hematoma left intact in a closed cavity for more than 6 months. This is an extremely rare case of chyliform fluid documented in an ICD pocket.

A challenging pacemaker implantation in the presence of a giant right coronary aneurysm compressing the right atrium.

Giant coronary artery aneurysm is an uncommon disease, treated with surgical intervention or percutaneous coil embolization. A thrombosed aneurysm can cause extrinsic compression on the cardiac chambers, with potential hemodynamic effects and may cause problems when we need to implant a cardiac device. We present a case of difficult pacemaker implantation in a patient with 3 syncopes, first-degree AV block and complete left bundle branch block on electrocardiogram. The patient presented a giant aneurysm of the right coronary artery (85 x 90 mm), thrombosed, with right atrial compression. The pacemaker implantation was hampered by the difficulty of passing the lead through the compressed right atrium; indeed, only with simultaneous echocardiographic and fluoroscopic guidance, was it possible to complete the procedure. This case demonstrates the utility of echocardiogram, in particular settings, in cardiac stimulation procedures.

Emergence of Electric Fields at the Water-C12E6 Surfactant Interface.

We study the properties of the interface of water and the surfactant hexaethylene glycol monododecyl ether (C12E6) with a combination of heterodyne-detected vibrational sum frequency generation (HD-VSFG), Kelvin-probe measurements, and molecular dynamics (MD) simulations. We observe that the addition of the hydrogen-bonding surfactant C12E6, close to the critical micelle concentration (CMC), induces a drastic enhancement in the hydrogen bond strength of the water molecules close to the interface, as well as a flip in their net orientation. The mutual orientation of the water and C12E6 molecules leads to the emergence of a broad (∼3 nm) interface with a large electric field of ∼1 V/nm, as evidenced by the Kelvin-probe measurements and MD simulations. Our findings may open the door for the design of novel electric-field-tuned catalytic and light-harvesting systems anchored at the water-surfactant-air interface.

Effect of water nanoconfinement on the dynamic properties of paramagnetic colloidal complexes.

The anomalous behavior of confined water at the nanoscale has remarkable implications in a number of nanotechnological applications. In this work, we analyze the effect of water self-diffusion on the dynamic properties of a solvated gadolinium-based paramagnetic complex, typically used for contrast enhancement in magnetic resonance imaging. In particular, we examine the effect of silica-based nanostructures on water behavior in the proximity of the paramagnetic complex via atomistic simulations, and interpret the resulting tumbling dynamics in the light of the local solvent modification based on the Lipari-Szabo formalism and of the fractional Stokes-Einstein relation. It is found that the local water confinement induces an increased "stiffness" on the outer sphere of the paramagnetic complex, which eventually reduces its tumbling properties. These model predictions are found to explain well the relaxivity enhancement observed experimentally by confining paramagnetic complexes into porous nanoconstructs, and thus offer mechanistic guidelines to design improved contrast agents for imaging applications.

Takotsubo syndrome and pheochromocytoma: an insidious combination.

Pheochromocytoma is a rare adrenal tumor characterized by the secretion of catecholamines and vasoactive peptides. It can cause a catecholaminergic storm and lead to acute coronary syndromes. We present the case of a 53-year-old man, without any medical history, who arrived to the hospital following a spinal trauma due a fall. He presents back and retrosternal pain, with a clinical status of acute pulmonary edema, sinus tachycardia with left bundle branch block, left ventricular apical ballooning with depressed systolic function. Blood tests show a very important increase of Troponin and transaminases. A contrast chest-abdomen CT highlighted a right adrenal solid mass, with a diameter of 78mm, partial capsular laceration, compression of the inferior vena cava and the hepatic parenchyma. The clinical condition of the patient rapidly worsens from a respiratory and hemodynamic point of view, with cardiogenic shock, anuria and sepsis, refractory to all the medical treatments, until the patient died. The autopsy confirmed that the abdominal mass was a pheochromocytoma, broken after the trauma suffered. The resulting catecholaminergic storm caused a myocardial ischemia with Takotsubo syndrome, with cardiogenic shock. This unfortunate case confirms the pheochromocytoma as important risk factor for the onset of Takotsubo syndrome, and the how dramatic and severe a catecholaminergic storm can be.

Therapeutic management of ventricular arrhythmias in Andersen-Tawil syndrome.

Andersen-Tawil Syndrome (ATS) is a rare periodic paralysis with typical skeletal and neuromuscular features. Cardiac involvement may range from asymptomatic ventricular arrhythmias to sudden death. Its management remains challenging and the choice between antiarrhythmic drug therapy and implantable cardioverter defibrillator (ICD) is not simple. We present a case of ATS patient with episodes of bidirectional ventricular tachycardia, well controlled by flecainide therapy initially, which in particular conditions of fever and hypokaliemia had a cardiac arrest with ventricular fibrillation, with neurological sequelae and need of an ICD implant. A review of the therapeutic management of this disease is presented.

Nano-metering of Solvated Biomolecules Or Nanoparticles from Water Self-Diffusivity in Bio-inspired Nanopores.

Taking inspiration from the structure of diatom algae frustules and motivated by the need for new detecting strategies for emerging nanopollutants in water, we analyze the potential of nanoporous silica tablets as metering devices for the concentration of biomolecules or nanoparticles in water. The concept relies on the different diffusion behavior that water molecules exhibit in bulk and nanoconfined conditions, e.g., in nanopores. In this latter situation, the self-diffusion coefficient of water reduces according to the geometry and surface properties of the pore and to the concentration of suspended biomolecules or nanoparticles in the pore, as extensively demonstrated in a previous study. Thus, for a given pore-liquid system, the self-diffusivity of water in nanopores filled with biomolecules or nanoparticles provides an indirect measure of their concentration. Using molecular dynamics and previous results from the literature, we demonstrate the correlation between the self-diffusion coefficient of water in silica nanopores and the concentration of proteins or nanoparticles contained therein. Finally, we estimate the time required for the nanoparticles to fill the nanopores, in order to assess the practical feasibility of the overall nano-metering protocol. Results show that the proposed approach may represent an alternative method for assessing the concentration of some classes of nanopollutants or biomolecules in water.

An atypical case of Stanford type-A chronic aortic dissection managed conservatively.

Stanford type-A aortic dissection is a clinical emergency; mortality is high, and surgery is urgently required in most cases. Chronic forms of type-A dissection are rare and have a poor prognosis if not treated surgically. We present an unusual case of chronic type-A aortic dissection, with silent onset, in an oncologic patient without risk factors, which was managed conservatively and remained substantially stable during follow-up.

From GROMACS to LAMMPS: GRO2LAM : A converter for molecular dynamics software.

Atomistic simulations have progressively attracted attention in the study of physical-chemical properties of innovative nanomaterials. GROMACS and LAMMPS are currently the most widespread open-source software for molecular dynamics simulations thanks to their good flexibility, numerous functionalities and responsive community support. Nevertheless, the very different formats adopted for input and output files are limiting the possibility to transfer GROMACS simulations to LAMMPS. In this article, we present GRO2LAM, a modular and open-source Python 2.7 code for rapidly translating input files and parameters from GROMACS to LAMMPS format. The robustness of the tool has been assessed by comparing the simulation results obtained by GROMACS and LAMMPS, after the format conversion by GRO2LAM. Specifically, three nanoscale configurations of interest in both engineering and biomedical fields are studied, namely a carbon nanotube, an iron oxide nanoparticle, and a protein immersed in water. In perspective, GRO2LAM may be the first step to achieve a full interoperability between molecular dynamics software. This would allow to easily exploit their complementary potentialities and post-processing functionalities. Moreover, GRO2LAM could facilitate the cross-check of simulation results, guaranteeing the reproducibility of molecular dynamics models and testing their robustness. Graphical Abstract GRO2LAM, a modular and open-source Python code for rapidly translating input files and parameters from GROMACS to LAMMPS format.

Coffee-based colloids for direct solar absorption.

Despite their promising thermo-physical properties for direct solar absorption, carbon-based nanocolloids present some drawbacks, among which the unpleasant property of being potentially cytotoxic and harmful to the environment. In this work, a sustainable, stable and inexpensive colloid based on coffee is synthesized and its photo-thermal properties investigated. The proposed colloid consists of distilled water, Arabica coffee, glycerol and copper sulphate, which provide enhanced properties along with biocompatibility. The photo-thermal performance of the proposed fluid for direct solar absorption is analysed for different dilutions and compared with that of a traditional flat-plate collector. Tailor-made collectors, opportunely designed and realized via 3D-printing technique, were used for the experimental tests. The results obtained in field conditions, in good agreement with two different proposed models, show similar performance of the volumetric absorption using the proposed coffee-based colloids as compared to the classical systems based on a highly-absorbing surface. These results may encourage further investigations on simple, biocompatible and inexpensive colloids for direct solar absorption.

Mesoscopic Moment Equations for Heat Conduction: Characteristic Features and Slow-Fast Mode Decomposition.

In this work, we derive different systems of mesoscopic moment equations for the heat-conduction problem and analyze the basic features that they must hold. We discuss two- and three-equation systems, showing that the resulting mesoscopic equation from two-equation systems is of the telegraphist's type and complies with the Cattaneo equation in the Extended Irreversible Thermodynamics Framework. The solution of the proposed systems is analyzed, and it is shown that it accounts for two modes: a slow diffusive mode, and a fast advective mode. This latter additional mode makes them suitable for heat transfer phenomena on fast time-scales, such as high-frequency pulses and heat transfer in small-scale devices. We finally show that, if proper initial conditions are provided, the advective mode disappears, and the solution of the system tends asymptotically to the transient solution of the classical parabolic heat-conduction equation.

Left atrial compression with acute heart failure caused by esophageal bolus.

We report a case of left atrial extrinsic compression caused by an esophageal food bolus in a patient presenting with acute heart failure. Transthoracic echocardiography along with contrast-enhanced CT showed evidence of esophageal dilation producing left atrial compression. Esophageal endoscopy and fragmentation of the bolus, allowing the accumulated food to descend into the stomach, produced a rapid improvement of hemodynamic and clinical status. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:259-261, 2018.

Prognostic value of total atrial conduction time measured with tissue Doppler imaging to predict the maintenance of sinus rhythm after external electrical cardioversion of persistent atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia, with a high recurrence rate, especially during the first months after cardioversion (CV). Few parameters have been evaluated as predictors for the maintenance of sinus rhythm (SR), with limited results. Recently total atrial conduction time (TACT) has been proposed as independent predictor of AF recurrence. The aim of this study was to investigate the prognostic value of TACT, measured using PA-TDI duration, to predict 1-year maintenance of restored SR after electrical CV. METHODS AND RESULTS: In a population of 104 patients (58 male, aged 70 ± 9) with persistent AF, submitted to external electrical CV, we performed a complete echocardiogram after restoring SR. The TACT was estimated by measuring the time delay between the onset of the P-wave in lead II of the surface electrocardiogram and the peak A'-wave on the tissue Doppler imaging (TDI) tracing of the left atrial lateral wall (so-called PA-TDI duration). After a mean follow-up of 14 ± 2 months, 34 (33%) patients had recurrent AF, whereas 70 (67%) patients maintained SR. At multivariate analysis only PA-TDI was identified as independent predictor of AF recurrence (HR 1.04; 95% CI 1.03-1.06; P < 0.001). Receiver operator characteristics curve analyses demonstrated a high degree of discrimination (area under the curve 0.923); with a cut point of 152 msec, we obtain a good diagnostic accuracy (sensitivity 91%, specificity 87%). CONCLUSION: The TACT using TDI is an independent predictor of AF recurrence and can be used to predict the maintenance of SR after external electrical CV.

Role of echocardiographic dyssynchrony parameters in predicting response to cardiac resynchronization therapy.

AIMS: In the present study, we compare different echocardiographic cardiac dyssynchrony parameters, both of intraventricular and interventricular dyssynchrony, in order to predict response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: In a population of 77 heart failure patients scheduled for CRT, we measured the interventricular mechanical delay (IVMD) and we analyzed six different parameters of intraventricular dyssynchony: the tissue Doppler imaging (TDI) septum-lateral wall delay, the systolic dyssynchrony index; the three-dimensional SD of the time to reach minimum systolic volume for 16 left ventricular segments (3D-SDI); the speckle-tracking radial, circumferential and longitudinal dyssynchrony. At 6 months of follow-up, 61 (79%) patients were responders (≤15% in left ventricular end-systolic volume). On baseline analysis, 3D-SDI, radial strain, longitudinal strain and circumferential strain and IVMD were significantly higher in responder group (10.8 ±â€Š3.9 vs. 7.6 ±â€Š1.8% for 3D-SDI; P = 0.003; 212 ±â€Š91 vs. 125 ±â€Š36 ms for radial strain, P = 0.0003; 185 ±â€Š83 vs. 134 ±â€Š53 ms for longitudinal strain, P = 0.02; 190 ±â€Š80 vs. 130 ±â€Š54 ms for circumferential strain, P = 0.006; 45 ±â€Š21 vs. 30 ±â€Š20 ms for IVMD; P = 0.01). On univariate and multivariate analysis, only IVMD was significantly associated with a complete echocardiographic response to CRT. 3D-SDI and radial strain present the better values of sensitivity and specificity, overall if associated to an evaluation of IVMD (sensitivity 76%, specificity 88%, for 3D-SDI + IVMD; sensitivity 80% and specificity 85% for radial strain + IVMD). CONCLUSION: The novel parameters, such as 3D-SDI and speckle-tracking (particularly radial strain), offer better diagnostic accuracy in identifying patients who are responders to CRT. The addition of the contemporary parameter of IVMD improves the diagnostic accuracy.

Isolated supravalvular pulmonary stenosis: a rare echocardiographic finding.

Isolated supravalvular pulmonary stenosis is a rare finding, usually evidenced in the pediatric age. Here, we report a case of a 76-year-old patient with isolated, severely obstructive, pulmonary supravalvular stenosis. The peculiarity of the present case is the paucity of symptoms and lack of changes in right heart sections, despite of the importance of stenosis. The report confirms the utility of transthoracic two- and three-dimensional echocardiography and transesophageal echocardiography in the detection and quantification of this rare anomaly.

[Herbs and cardiotoxic effects]. / Cardiotossicità da erbe selvatiche.

Accidental or deliberate ingestion of poisonous herbs has become an increasingly common phenomenon over the last years. From existing literature data and case reports from emergency room visits or poison control centers, an overview is presented of the potential cardiotoxic manifestations following intoxication by wild herbal plants of the territory. The effects of the consumption of cardiac glycoside-containing plants (e.g., digitalis) are discussed along with tachyarrhythmias induced by Aconitum napellus L., Atropa belladonna L., Mandragora officinarum L. or Ephedra distachya L. herbs, and hypertensive crises associated with licorice abuse. For each plant, a brief historical and botanical background is provided, focusing on pathophysiology of intoxication and cardiotoxic effects on the basis of the most recent literature. Finally, medical management of intoxication, from both a general and cardiological viewpoint, is reviewed.