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Non-invasive right ventricular (RV) myocardial work (MW) is a novel echocardiographic technique evaluating cardiac mechanics, contractility, and energetics beyond conventional echocardiographic measurements. This technique is an advancement of myocardial strain analysis and combines RV strain with loading conditions. It correlates well with invasively measured myocardial work and with myocardial oxygen consumption. RV MW is independent of afterload and seems best suitable for perioperative assessment of RV function. However, this technique has not yet been well described in the perioperative setting. Therefore, we aimed to evaluate this innovative method in the perioperative course of left ventricular assist device (LVAD) implantation and compare it to conventional echocardiographic and hemodynamic measurements. We conducted a retrospective analysis of all 78 patients that underwent LVAD implantation from January 2014 to January 2024 at our institution. 32 patients had echocardiographic images performed with echocardiographic machines and software appropriate for RV MW analysis, of whom ten patients had complete pre- and postoperative images required for estimation of RV MW indices. Transthoracic echocardiography (TTE) was completed during the preoperative evaluation (T1) and before discharge from hospital (T2), without any vasoactive support under stable hemodynamic conditions. EchoPAC v204 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of RV global work index (GWI), RV global constructive work (GCW), RV global wasted work (GWW), RV global work efficiency (GWE), RV global longitudinal strain (GLS), RV free-wall strain (FWS), longitudinal strain of the interventricular septum (IVS), RV fractional area change (FAC), and tricuspid annular systolic excursion (TAPSE). Moreover, RV filling pressures were estimated echocardiographically to evaluate loading conditions. RV contractile pattern changed significantly in our patient population through the perioperative course of LVAD implantation [T1 v T2]. RV free-wall longitudinal function decreased (FWS, -8.2% (IQR -5.7;-10.9) v -5.9% (IQR -5.2;-8.1), p=0.04; TAPSE, 16mm (IQR 14;20) v 9mm (IQR 8;11), p<0.01), while septal contribution and global RV function improved (IVS, -2.2% (IQR -1.5;-3.9) v -5.0% (IQR -3;-9), p=0.04; FAC, 25% (IQR 18;32) v 36% (24;43), p=0.03). RV MW analysis showed a reduction of RV effective (GWI, 212mmHg% (IQR 128;266) v 96mmHg% (IQR 63;150), p=0.02; GCW, 331mmHg% (IQR 263;476) v 198mmHg% (IQR 136;274), p<0.01) and ineffective myocardial work (GWW, 171mmHg% (IQR 102;243) v 98mmHg% (IQR 48;153), p=0.04), suggesting a reduction of RV myocardial oxygen consumption after device implantation. RV filling pressures declined, while RV efficiency remained unchanged (GWE, 69% (IQR 37;78) v 64% (IQR (61;78), p=0.26) in the same period. In conclusion, there was a change of RV contractile pattern in our patient population after LVAD implantation with a reduction of RV longitudinal function, which was compensated by an increase of RV circumferential contraction and interventricular septum contribution that even improved global RV function. Assessment of RV MW indices showed decreased RV myocardial workload after device implantation, suggesting a reduction of RV myocardial oxygen consumption in our patient population. RV MW is an evolving non-invasive technique providing deeper insights into perioperative RV energetics and could support individualized decision making in cardiac surgery patients. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is a promising technology for eco-friendly energy storage. However, the design principles for highly active, robust, and noble metal-free electrocatalysts for industrial-scale hydrogen production remain controversial. Oxygen-free compounds containing anionic species with a very high oxidation potential, such as fluorides, have emerged as high-performance targets for thermodynamically stable oxygen evolution reaction (OER) catalysts. They can further be designed to fit the key criteria of high electrical conductivity and stability. Herein, we present a facile and scalable etching method for constructing fluoride doped metallic nickel-based anodes from industrial Ni foam sources with high application potential for large-scale hydrogen production setups. The fluoride-etched Ni-catalysts were investigated with a wide range of techniques, such as powder X-ray diffraction (PXRD), extended X-ray absorption fine structure spectroscopy (EXAFS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). Optimized catalysts displayed a promising overpotential of 220 mV for the OER at a current density of 60 mA cm−2, which is competitive with noble metal-based reference catalysts, such as iridium oxide. Electrochemical impedance spectroscopy (EIS) studies demonstrated that etching of the electrode surface in fluoride medium leads to a drastic decrease of R ct. The corresponding decreased resistivity towards electrochemical OER on the electrode surface gives rise to the notably enhanced performance, with a minimum of synthetic effort. [Display omitted] • One-step hydrothermal etching process to prepare porous NiFOOH on Ni foam. • Fluorine-modified electrodes exhibit superior activity in OER. • Promising overpotential of 188 mV for the OER at a current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

New empirical formulae for in-medium nucleon-nucleon cross-section are presented and used to study the proton-nucleus interaction in the framework of Glauber model. The total, absorption and elastic cross-sections are calculated for many target nuclei. The calculated total cross-sections using the in-medium effective factor , f m 4 , give a reasonable fit with the experimental data. In addition, the in-medium factors f m 1 , f m 2 and f m 3 successfully reproduce the absorption cross-section at energies up to 600 MeV. [ABSTRACT FROM AUTHOR]

Purpose Unfavorable outcomes after trachomatous trichiasis (TT) surgery are undermining the global trachoma elimination effort. This analysis investigates predictors of postoperative TT (PTT), eyelid contour abnormalities (ECAs), and granuloma in the 2 most common TT surgery procedures: posterior lamellar tarsal rotation (PLTR) and bilamellar tarsal rotation (BLTR). Design Secondary data analysis from a randomized, controlled, single-masked clinical trial. Participants A total of 1000 patients with TT, with lashes touching the eye or evidence of epilation, in association with tarsal conjunctival scarring. Methods Participants were randomly allocated and received BLTR (n = 501) or PLTR (n = 499) surgery. Disease severity at baseline, surgical incisions, sutures, and corrections were graded during and immediately after surgery. Participants were examined at 6 and 12 months by assessors masked to allocation. Main Outcome Measures Predictors of PTT, ECA, and granuloma. Results Data were available for 992 (99.2%) trial participants (496 in each arm). There was strong evidence that performing more peripheral dissection with scissors in PLTR (odd ratio [OR], 0.70; 95% confidence interval [CI], 0.54–0.91; P = 0.008) and BLTR (OR, 0.83; 95% CI, 0.72–0.96; P = 0.01) independently protected against PTT. Baseline major trichiasis and mixed location lashes and immediate postoperative central undercorrection independently predicted PTT in both surgical procedures. Peripheral lashes in PLTR (OR, 5.91; 95% CI, 1.48–23.5; P = 0.01) and external central incision height ≥4 mm in BLTR (OR, 2.89; 95% CI, 1.55–5.41; P = 0.001) were independently associated with PTT. Suture interval asymmetry of >2 mm (OR, 3.18; 95% CI, 1.31–7.70; P = 0.01) in PLTR and baseline conjunctival scarring in BLTR (OR, 1.72; 95% CI, 1.06–2.81; P = 0.03) were independently associated with ECA. Older age was independently associated with ECA in both PLTR ( P value for trend < 0.0001) and BLTR ( P value for trend = 0.03). There was substantial intersurgeon variability in ECA rates for both PLTR (range, 19.0%–36.2%) and BLTR (range, 6.1%–28.7%) procedures. In PLTR surgery, irregular posterior lamellar incision at the center of the eyelid (OR, 6.72; 95% CI, 1.55–29.04; P = 0.01) and ECA (OR, 3.08; 95% CI, 1.37–6.94; P = 0.007) resulted in granuloma formation. Conclusions Poor postoperative outcomes in TT surgery were associated with inadequate peripheral dissection, irregular incision, asymmetric suture position and tension, inadequate correction, and lash location. Addressing these will improve TT surgical outcomes. [ABSTRACT FROM AUTHOR]