Prediction of Major Arrhythmic Outcomes in Ischemic Cardiomyopathy: Value of Hibernating Myocardium in PET/CT

AIMS: Known predictors of major arrhythmic events (MAE) in patients with ischemic cardiomyopathy (ICM) include previous MAE and left ventricular ejection fraction (LVEF) ≤35%. Myocardial scars detected by perfusion imaging in ICM have been linked to MAE, but the prognostic significance of hibernating myocardium (HM) is unclear. The objective was to predict major arrhythmic events (MAE) from combined 13N-ammonia (NH3) and 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in ischemic cardiomyopathy (ICM). METHODS AND RESULTS: Consecutive patients with ICM undergoing combined NH3- and FDG-PET/CT were included. HM was quantified in relation to total left ventricular myocardium (i.e. ≥7% is large). The primary outcome was MAE (sudden cardiac death, ICD therapy, sustained ventricular tachycardia/fibrillation).Among 254 patients, median baseline LVEF was 35% (IQR 28-45) and 10% had an ICD. PET/CT identified ischemia in 94 (37%), scar in 229 (90%) and HM in 195 (77%) patients. Over a median follow-up of 5.4 (IQR 2.2-9.5) years, MAE occurred in 34 patients (13%). Large HM was associated with a lower incidence of MAE (HR 0.31, 95% CI 0.1-0.8, p=0.001). After multivariate adjustment for history of MAE, LVEF ≤35% and scar ≥10%, large HM remained significantly associated with a lower incidence of MAE (p=0.016). LVEF improved over time among patients with large HM (p=0.006) but did not change in those without (p=0.610) or small HM (p=0.240). CONCLUSIONS: HM conveys a lower risk of MAE in patients with ICM. This may be explained by an increase in LVEF when a large extent of HM is present

Wireless power distributions in multi-cavity systems at high frequencies

The next generations of wireless networks will work in frequency bands ranging from sub-6 GHz up to 100 GHz. Radio signal propagation differs here in several critical aspects from the behaviour in the microwave frequencies currently used. With wavelengths in the millimetre range (mmWave), both penetration loss and free-space path loss increase, while specular reflection will dominate over diffraction as an important propagation channel. Thus, current channel model protocols used for the generation of mobile networks and based on statistical parameter distributions obtained from measurements become insufficient due to the lack of deterministic information about the surroundings of the base station and the receiver-devices. These challenges call for new modelling tools for channel modelling which work in the short-wavelength/high-frequency limit and incorporate site-specific details—both indoors and outdoors. Typical high-frequency tools used in this context—besides purely statistical approaches—are based on ray-tracing techniques. Ray-tracing can become challenging when multiple reflections dominate. In this context, mesh-based energy flow methods have become popular in recent years. In this study, we compare the two approaches both in terms of accuracy and efficiency and benchmark them against traditional power balance methods

The GRAVITY young stellar object survey: VIII. Gas and dust faint inner rings in the hybrid disk of HD141569

Stars and planetary system

The ABSCISIC ACID-INSENSITIVE3, FUSCA3, and LEAFY COTYLEDON1 loci act in concert to control multiple aspects of Arabidopsis seed development.

Previous studies have shown that recessive mutations at the Arabidopsis ABSCISIC ACID-INSENSITIVE3 (ABI3), FUSCA3 (FUS3), and LEAFY COTYLEDON1 (LEC1) loci lead to various abnormalities during mid-embryogenesis and late embryogenesis. In this study, we investigated whether these loci act in independent regulatory pathways or interact in controlling certain facets of seed development. Several developmental responses were quantified in abi3, fus3, and lec1 single mutants as well as in double mutants combining either the weak abi3-1 or the severe abi3-4 mutations with either fus3 or lec1 mutations. Our data indicate that ABI3 interacts genetically with both FUS3 and LEC1 in controlling each of the elementary processes analyzed, namely, accumulation of chlorophyll and anthocyanins, sensitivity to abscisic acid, and expression of individual members of the 12S storage protein gene family. In addition, both FUS3 and LEC1 regulate positively the abundance of the ABI3 protein in the seed. These results suggest that in contrast to previous models, the ABI3, FUS3, and LEC1 genes act synergistically to control multiple elementary processes during seed development

Regulation of gene expression programs during Arabidopsis seed development: roles of the ABI3 locus and of endogenous abscisic acid.

The accumulation kinetics of 18 mRNAs were characterized during Arabidopsis silique development. These marker mRNAs could be grouped in distinct classes according to their coordinate temporal expression in the wild type and provided a basis for further characterization of the corresponding regulatory pathways. The abscisic acid (ABA)-insensitive abi3-4 mutation modified the expression pattern of several but not all members of each of these wild-type temporal mRNA classes. This indicates that the ABI3 protein directly participates in the regulation of several developmental programs and that multiple regulatory pathways can lead to the simultaneous expression of distinct mRNA markers. The ABI3 gene is specifically expressed in seed, but ectopic expression of ABI3 conferred the ability to accumulate several seed-specific mRNA markers in response to ABA in transgenic plantlets. This suggested that expression of these marker mRNAs might be controlled by an ABI3-dependent and ABA-dependent pathway(s) in seed. However, characterization of the ABA-biosynthetic aba mutant revealed that the accumulation of these mRNAs is not correlated to the ABA content of seed. A possible means of regulating gene expression by developmental variations in ABA sensitivity is apparently not attributable to variations in ABI3 cellular abundance. The total content of ABI3 protein per seed markedly increased at certain developmental stages, but this augmentation appears to result primarily from the simultaneous multiplication of embryonic cells. Our current findings are discussed in relation to their general implications for the mechanisms controlling gene expression programs in seed

Binary mixture effects by PBDE congeners (47, 153, 183 or 209) and PCB congeners (126 or 153) in MCF-7 cells: biochemical alterations assessed by IR spectroscopy and multivariate analysis

Target organisms are continuously and variously exposed to contaminant mixtures in the environment. We noted that treatment with brominated diphenyl ether (BDE)47 or polychlorinated biphenyl (PCB)126 (toxic equivalency factor [TEF] = 0.1) induces similar alterations in MCF-7 cells when these were determined using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy with multivariate analysis. Because this method appears sensitive enough to signature low-dose effects, we examined how various test agents interact in binary mixtures to induce cell alterations. MCF-7 cells were exposed for 24 h to low concentrations (10−12 M) of polybrominated diphenyl ether (PBDE) congeners (47, 153, 183, or 209) with or without the coplanar PCB126 or nonplanar PCB153. Following treatment, ethanol-fixed cellular material was interrogated using ATR-FTIR spectroscopy; derived IR spectra in the biochemical-cell fingerprint region (1800 cm−1−900 cm−1) were then subjected to principal component analysis-linear discriminant analysis. Assuming that if two test agents independently induce the same cell alteration that in combination they’ll give rise to an additive effect, we examined predicted versus observed differences in induced alterations by binary mixtures. Compared to corresponding control clusters, treatment with PBDE congener plus PCB126 appeared to cancel out their respective induced alterations. However, treatment with binary mixtures including PCB153 gave rise to an enhanced segregation. Our findings suggest that test agents which mediate their cellular effects via similar mechanisms might result in inhibition within a binary mixture whereas independently acting agents could exacerbate induced alterations in overall cell status

ALMA reveals a large structured disk and nested rotating outflows in DG Tauri B

We present Atacama Large Millimeter Array (ALMA) Band 6 observations at 14−20 au spatial resolution of the disk and CO(2-1) outflow around the Class I protostar DG Tau B in Taurus. The disk is very large, both in dust continuum (Reff, 95% = 174 au) and CO (RCO = 700 au). It shows Keplerian rotation around a 1.1 ± 0.2 M⊙ central star and two dust emission bumps at r = 62 and 135 au. These results confirm that large structured disks can form at an early stage where residual infall is still ongoing. The redshifted CO outflow at high velocity shows a striking hollow cone morphology out to 3000 au with a shear-like velocity structure within the cone walls. These walls coincide with the scattered light cavity, and they appear to be rooted within 70°). The properties of the conical walls are suggestive of the interaction between an episodic inner jet or wind with an outer disk wind, or of a massive disk wind originating from 2 to 5 au. However, further modeling is required to establish their origin. In either case, such massive outflow may significantly affect the disk structure and evolution