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Two-dimensional materials with high charge carrier mobility and tunable band gaps have attracted intense research effort for their potential use in nanoelectronics. Two-dimensional π-conjugated polymers constitute a promising subclass because the band structure can be manipulated by varying the molecular building blocks while preserving key features such as Dirac cones and high charge mobility. The major barriers to the application of two-dimensional π-conjugated polymers have been the small domain size and high defect density attained in the syntheses explored so far. Here, we demonstrate the fabrication of mesoscale ordered two-dimensional π-conjugated polymer kagome lattices with semiconducting properties, Dirac cone structures and flat bands on Au(111). This material has been obtained by combining a rigid azatriangulene precursor and a hot dosing approach, which favours molecular diffusion and eliminates voids in the network. These results open opportunities for the synthesis of two-dimensional π-conjugated polymer Dirac cone materials and their integration into devices. Optimized Ullmann coupling reaction of heterotriangulene precursors allows the synthesis of two-dimensional π-conjugated polymers with ordered domains larger than 100 × 100 nm 2 showing both Dirac cones and flat bands in their electronic structure.

Transcatheter aortic valve implantation (TAVI) has become the standard of care in elderly high-risk patients with symptomatic severe aortic stenosis. Recently, TAVI has been increasingly performed in younger-, intermediate- and lower-risk populations, which underlines the need to investigate the long-term durability of bioprosthetic aortic valves. However, diagnosing bioprosthetic valve dysfunction after TAVI is challenging and only limited evidence-based criteria exist to guide therapy. Bioprosthetic valve dysfunction encompasses structural valve deterioration (SVD) resulting from degenerative changes in the valve structure and function, non-SVD resulting from intrinsic paravalvular regurgitation or patient–prosthesis mismatch, valve thrombosis, and infective endocarditis. Overlapping phenotypes, confluent pathologies, and their shared end-stage bioprosthetic valve failure complicate the differentiation of these entities. In this review, we focus on the contemporary and future roles, advantages, and limitations of imaging modalities such as echocardiography, cardiac computed tomography angiography, cardiac magnetic resonance imaging, and positron emission tomography to monitor the integrity of transcatheter heart valves.

The Mercury Orbiter Radio Science Experiment (MORE) of the ESA mission BepiColombo will provide an accurate estimation of Mercury’s gravity field and rotational state, improved tests of general relativity, and a novel deep space navigation system. The key experimental setup entails a highly stable, multi-frequency radio link in X and Ka band, enabling two-way range rate measurements of 3 micron/s at nearly all solar elongation angles. In addition, a high chip rate, pseudo-noise ranging system has already been tested at 1-2 cm accuracy. The tracking data will be used together with the measurements of the Italian Spring Accelerometer to provide a pseudo drag free environment for the data analysis. We summarize the existing literature published over the past years and report on the overall configuration of the experiment, its operations in cruise and at Mercury, and the expected scientific results.

Background Given that the pathogenetic process of ALS begins many years prior to its clinical onset, examining patients’ residential histories may offer insights on the disease risk factors. Here, we analyzed the spatial distribution of a large ALS cohort in the 50 years preceding the disease onset. Methods Data from the PARALS register were used. A spatial cluster analysis was performed at the time of disease onset and at 1-year intervals up to 50 years prior to that. Results A total of 1124 patients were included. The analysis revealed a higher-incidence cluster in a large area (435,000 inhabitants) west of Turin. From 9 to 2 years before their onset, 105 cases were expected and 150 were observed, resulting in a relative risk of 1.49 ( P  = 0.04). We also found a surprising high number of patients pairs (51) and trios (3) who lived in the same dwelling while not being related. Noticeably, these occurrences were not observed in large dwellings as we would have expected. The probability of this occurring in smaller buildings only by chance was very low ( P  = 0.01 and P  = 0.04 for pairs and trios, respectively). Conclusions We identified a higher-incidence ALS cluster in the years preceding the disease onset. The cluster area being densely populated, many exposures could have contributed to the high incidence ALS cluster, while we could not find a shared exposure among the dwellings where multiple patients had lived. However, these findings support that exogenous factors are likely involved in the ALS pathogenesis.

The aim of our study was to evaluate 3-dimensional (3D) color Doppler proximal isovelocity surface area (PISA) as a tool for quantitative assessment of mitral regurgitation (MR) against in vitro and in vivo reference methods. A customized 3D PISA software was validated in vitro against a flowmeter MR phantom. Sixty consecutive patients, with ≥mild MR of any cause, were recruited and the regurgitant volume (RVol) was measured by 2D PISA, 3D peak PISA, and 3D integrated PISA, using transthoracic (TTE) and transesophageal echocardiography (TEE). Cardiac magnetic resonance imaging (CMR) was used as reference method. Flowmeter RVol was associated with 3D integrated PISA as follows: y = 0.64x + 4.7, r2 = 0.97, p <0.0001 for TEE and y = 0.88x + 4.07, r2 = 0.96, p <0.0001 for TTE. The bias and limit of agreement in the Bland–Altman analysis were 6.8 ml [−3.5 to 17.1] for TEE and −0.059 ml [−6.2 to 6.1] for TTE. In vivo, TEE-derived 3D integrated PISA was the most accurate method for MR quantification compared to CMR: r2 = 0.76, y = 0.95x − 3.95, p <0.0001; 5.1 ml (−14.7 to 26.5). It was superior to TEE 3D peak PISA (r2 = 0.67, y = 1.00x + 6.20, p <0.0001; −6.3 ml [−33.4 to 21.0]), TEE 2D PISA (r2 = 0.54, y = 0.76x + 0.18, p <0.0001; 8.4 ml [−20.4 to 37.2]), and TTE-derived measurements. It was also most accurate by receiver operating characteristic analysis (area under the curve 0.99) for the detection of severe MR, RVol cutoff = 48 ml, sensibility 100%, and specificity 96%. RVol and the cutoff to define severe MR were underestimated using the most accurate method. In conclusion, quantitative 3D color Doppler echocardiography of the PISA permits a more accurate MR assessment than conventional techniques and, consequently, should enable an optimized management of patients suffering from MR.

ObjectiveA consequence in patients with d-transposition of the great arteries (d-TGA) and tetralogy of Fallot (TOF) is right ventricular hypertrophy (RVH) and right ventricular failure. Myocardial contrast echocardiography (MCE) permits the determination of the myocardial microvascular density reflected by the relative myocardial blood volume (rBV; ml/ml). This study was conducted to elucidate the relationship between RVH and myocardial microvascular changes by quantitative MCE in patients with d-TGA and TOF.MethodsThree groups of individuals were included in the study: 22 patients with d-TGA, 18 patients with TOF and 22 healthy individuals (controls). MCE was performed at rest and during adenosine-induced hyperaemia. rBV and myocardial blood flow (MBF; ml/min per gram) were derived from steady state and refill sequences of ultrasound contrast agent.ResultsHyperaemic septal rBV differed significantly between the groups and was highest in controls: d-TGA 0.141±0.060 ml/ml, TOF 0.134±0.080 ml/ml, controls 0.189±0.074 ml/ml, p=0.005. Myocardial blood flow reserve (MBFR), that is the ratio of hyperaemic to baseline MBF, differed significantly between the groups and was lowest in d-TGA (2.68±1.13) versus TOF (3.37±1.57) and controls (4.22±1.17, p=0.001). Hyperaemic septal rBV, MBF and MBFR showed a significant correlation with right ventricular systolic function as determined by tricuspid annular plane systolic excursion.ConclusionsRight ventricular myocardial microvascular density of the septal wall in d-TGA and TOF patients with RVH due to pressure and/or volume overload is reduced. This appears to be related to a reduced myocardial perfusion reserve and impaired right ventricular systolic function.

OBJECTIVE To determine the pulmonary venous flow velocity (PVFV) values in a large normal population. DESIGN Prospective study in consecutive individuals. SETTING University hospital. METHODS Among 404 normal individuals, the flow velocity pattern in the right upper pulmonary vein was recorded in 315 subjects using transthoracic echocardiography, and in both upper pulmonary veins in 100 subjects using transoesophageal echocardiography. Subjects were divided into five age groups. The PVFV values were compared between transthoracic and transoesophageal echocardiography within the age groups, and intraindividually between the right and left upper pulmonary veins in transoesophageal echocardiography. RESULTS Normal PVFV values for the right upper pulmonary vein in transthoracic and transoesophageal echocardiography are presented. The duration of flow reversal at atrial contraction was overestimated using transthoracic echocardiography (mean (SD): 96 (21) ms in transoesophageal echocardiography, 120 (28) ms in transthoracic echocardiography, p < 0.0001). Systolic to diastolic peak flow velocity ratio (S:D) increased earlier with advancing age with transoesophageal echocardiography than with transthoracic echocardiography. Similar results were found for the corresponding time–velocity integrals. Data from the left and right upper pulmonary veins differed with respect to onset and deceleration of flow velocities, but not for flow durations or peak velocities. CONCLUSIONS Normal PVFV values generally show a wide range. The data presented will be of value in assessing left ventricular diastolic function and mitral regurgitation using the PVFV pattern.

BackgroundThe efficacy of external counterpulsation (ECP) on coronary collateral growth has not been investigated in a randomised controlled study.ObjectiveTo test the hypothesis that ECP augments collateral function during a 1 min coronary balloon occlusion.Patients and methodsTwenty patients with chronic stable coronary artery disease were studied. Before and after 30 h of randomly allocated ECP (20 90 min sessions over 4 weeks at 300 mm Hg inflation pressure) or sham ECP (same setting at 80 mm Hg inflation pressure), the invasive collateral flow index (CFI, no unit) was obtained in 34 vessels without coronary intervention. CFI was determined by the ratio of mean distal coronary occlusive pressure to mean aortic pressure with central venous pressure subtracted from both. Additionally, coronary collateral conductance (occlusive myocardial blood flow per aorto-coronary pressure drop) was determined by myocardial contrast echocardiography, and brachial artery flow-mediated dilatation was obtained.ResultsCFI changed from 0.125 (0.073; interquartile range) at baseline to 0.174 (0.104) at follow-up in the ECP group (p=0.006), and from 0.129 (0.122) to 0.111 (0.125) in the sham ECP group (p=0.14). Baseline to follow-up change of coronary collateral conductance was from 0.365 (0.268) to 0.568 (0.585) ml/min/100 mm Hg in the ECP group (p=0.072), and from 0.229 (0.212) to 0.305 (0.422) ml/min/100 mm Hg in the sham ECP group (p=0.45). There was a correlation between the flow-mediated dilatation change from baseline to follow-up and the corresponding CFI change (r=0.584, p=0.027).ConclusionsECP appears to be effective in promoting coronary collateral growth. The extent of collateral function improvement is related to the amount of improvement in the systemic endothelial function.

Background The aim of this prospective, double‐blinded study in patients with aortic sclerosis was to determine whether a new calcification propensity measure in the serum could predict disease progression. Methods We included 129 consecutive patients with aortic sclerosis as assessed during a routine clinical echocardiographic exam. Clinical, echocardiographic, and serum laboratory parameters were collected, including a new blood test providing an overall measure of calcification propensity by monitoring the maturation time of calciprotein particles (T50 test). The echocardiographic exam was repeated after 1 year. Multiple regression analysis was performed to identify independent predictors of the annual increase of peak transvalvular Doppler velocity (∆vmax). Furthermore, the accuracy of the T50 test to detect patients with the most marked stenosis progression was assessed by receiver operating characteristic (ROC)‐analysis. Results Mean age was 75 ± 9 years, 79% were men. The T50 was 271 ± 58 min. Overall, there was no significant stenosis progression between baseline and follow‐up (∆vmax 3.8 ± 29.8 cm/s, p = ns). The T50 test was not found to be an independent linear predictor in multivariate testing. By ROC‐analysis, however, a T50‐value ≤ 242 min was able to significantly detect a ∆vmax above the 90th percentile (∆vmax ≥ 43 cm/s, AUC = 0.67, p = .04, Sensitivity = 69%, Specificity = 70%). Conclusions The T50 test showed a modest but significant ability to identify a pronounced aortic stenosis progression in patients with aortic sclerosis. The test could not be established as an independent linear predictor of disease progression, possibly due to the low valvular disease burden and short follow‐up interval.

Background Visual hallucinations (VHs) are frequent non-motor complication of Parkinson’s disease (PD), associated to a negative prognosis. Previous studies showed an association between dopamine receptor (DR) gene ( DR ) variants and psychosis in Alzheimer’s disease, addictions, schizophrenia, and bipolar disorder. However, there are only a few studies on DR variants and VHs in PD, which did not provide conclusive results. Objectives The present study aimed to determine whether genetic differences of DR are associated with visual hallucinations (VHs) in a cohort of Parkinson’s disease (PD) patients. Methods A case-control study of 84 PD subjects, 42 with and 42 without VHs,that were matched for age, gender, disease duration, and dopaminergic medication was conducted. Polymerase chain reaction for SNPs in both D1-like ( DRD1 A-48G [rs4532] and C62T [rs686], DRD5T798C [rs6283]) and D2-like DR ( DRD2 G2137A [rs1800497] and C957T [rs6277], DRD3 G25A [rs6280] and G712C [rs1800828], DRD4 C616G [rs747302] and nR VNTR 48bp) analyzed genomic DNA. Results Patients carrying allele T at DRD1 C62T had an increased risk of VHs, expressed as OR (95 % CI, p value), of 10.7 (2.9–40, p  = 0.0001). Moreover, patients with DRD1 -48 GG and 62TT genotype displayed shorter time to VHs, whereas a longer time to VHs was found in subjects carrying the DRD4 CG alleles. Conclusions PD patients with VHs display higher frequency of DR SNPs associated with increased D1-like activity and decreased D2-like activity. Our data are in line with associations reported in other neurodegenerative and psychiatric conditions. Results likely provide valuable information for personalizing pharmacological therapy in PD patients.