Angiotensin receptor blocker-neprilysin inhibitor (ARNi) therapy improves the prognosis of heart failure patients. However, the mechanisms remain unclear. This study investigated the biological ...effects of ARNi with neprilysin inhibitor sacubitril and angiotensin receptor blocker valsartan on myocardial remodeling and cardiac perfusion in experimental heart failure (HF) after myocardial infarction (MI). Male Lewis rats (10-weeks old) with confirmed HF were randomized one-week post-MI to treatment with vehicle (water), sacubitril/valsartan or valsartan, as comparator group, for either 1 or 5 weeks. Sacubitril/valsartan for 1-week limited LV contractile dysfunction vs. vehicle and both sacubitril/valsartan and valsartan attenuated progressive LV dilation after 1 and 5 weeks treatment. After 5 weeks, both sacubitril/valsartan and valsartan reduced CTGF expression in the remote myocardium, although only sacubitril/valsartan prevented interstitial fibrosis. In the border zone, sacubitril/valsartan and valsartan reduced hypertrophic markers, but only sacubitril/valsartan reduced cardiomyocyte size and increased VEGFA expression. In the infarct, sacubitril/valsartan induced an early uptake of
Tc-NC100692 (a radiotracer of angiogenesis) and improved perfusion, as determined by
Tl microSPECT/CT imaging. In conclusion, ARNi improved global LV function, limited remodeling in the remote and border zones, and increased perfusion to the infarct. Sacubitril/valsartan had more consistent effects than valsartan on LV remodeling in experimental HF.
To examine the effectiveness of Brains Ahead!, a psychoeducational intervention aimed to prevent long-term problems with activities and participation in children after mild traumatic brain injury ...(mTBI).
In total, 124 children, aged 6 to 18 years, diagnosed with mTBI and their caregivers.
After randomization, participants in the intervention group received a face-to-face psychoeducational session with written take-home information and follow-up telephone call(s). Participants in the control group received usual care, consisting of a concise information brochure.
Activities and participation (Child and Adolescent Scale of Participation CASP).
fatigue, postconcussive symptoms (PCSs), posttraumatic stress symptoms (PTSSs), and quality of life (QOL).
Generalized Estimated Equation analyses showed that both groups improved over the first 6 months post-mTBI, but the intervention group did not differ significantly on the CASP. Mann-Whitney U tests showed that the intervention group reported significantly less fatigue, PCSs, and PTSSs and better QOL compared with the control group at 6 months post-MTBI.
The Brains Ahead! intervention resulted in significant improvements compared with usual care in reducing fatigue, PCSs, and PTSSs and improving QOL. Lack of an effect on activities and participation may be due to the ceiling effect of the CASP.
The evolution of the levels of tobacco-specific N-nitrosamines (TSNA), N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in mainstream (MS) cigarette smoke is ...investigated based on smoke and tobacco chemistry data of cigarette brands sold by Philip Morris International (PMI) between 2000 and 2014. A total of 315 cigarette samples representing a wide range of product and design characteristics manufactured by PMI between 2008 and 2014 were analyzed and compared to a previously published dataset of PMI brands manufactured in 2000. The data indicate that there is a substantial reduction of NNN and NNK levels in tobacco fillers and MS cigarette smoke per mg of tar and per mg of nicotine using Health Canada Intense (HCI) machine-smoking regime. This observed reduction in NNN and NNK levels in MS cigarette smoke is also supported by the downward trend observed on NNN and NNK levels in USA flue-cured Virginia and Burley tobacco lots from 2000 to 2014 crops, reflecting effectiveness of measures taken on curing and agricultural practices designed to minimize TSNA formation in tobacco.
•Tobacco specific nitrosamines, NNN and NNK, in cigarette smoke and tobacco filler across 2000 to 2014 were investigated.•The data indicate a substantial reduction of both NNN and NNK in tobacco filler and cigarette smoke.•Downward trend observed on NNN and NNK levels overlap with measures taken to reduce TSNA formation in tobacco.
Context. While supernova remnants (SNRs) have been considered the most relevant Galactic cosmic ray (CR) accelerators for decades, core-collapse supernovae (CCSNe) could accelerate particles during ...the earliest stages of their evolution and hence contribute to the CR energy budget in the Galaxy. Some SNRs have indeed been associated with TeV γ -rays, yet proton acceleration efficiency during the early stages of an SN expansion remains mostly unconstrained. Aims. The multi-wavelength observation of SN 2023ixf, a Type II supernova (SN) in the nearby galaxy M 101 (at a distance of 6.85 Mpc), opens the possibility to constrain CR acceleration within a few days after the collapse of the red super-giant stellar progenitor. With this work, we intend to provide a phenomenological, quasi-model-independent constraint on the CR acceleration efficiency during this event at photon energies above 100 MeV. Methods. We performed a maximum-likelihood analysis of γ -ray data from the Fermi Large Area Telescope up to one month after the SN explosion. We searched for high-energy, non-thermal emission from its expanding shock, and estimated the underlying hadronic CR energy reservoir assuming a power-law proton distribution consistent with standard diffusive shock acceleration. Results. We do not find significant γ -ray emission from SN 2023ixf. Nonetheless, our non-detection provides the first limit on the energy transferred to the population of hadronic CRs during the very early expansion of a CCSN. Conclusions. Under reasonable assumptions, our limits would imply a maximum efficiency on the CR acceleration of as low as 1%, which is inconsistent with the common estimate of 10% in generic SNe. However, this result is highly dependent on the assumed geometry of the circumstellar medium, and could be relaxed back to 10% by challenging spherical symmetry. Consequently, a more sophisticated, inhomogeneous characterisation of the shock and the progenitor’s environment is required before establishing whether or not Type II SNe are indeed efficient CR accelerators at early times.
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•A field study assessed the effects of organic wastes on soil and ryegrass growth.•Plant parameters were more positively affected after sewage sludge application.•After two years, ...soil parameters were more positively affected by composts.•Soil total and extractable Cd, Cr, Ni and Pb did not increase, but Cu and Zn did.•Trace elements in the plant were lower than maximum tolerable levels for cattle.
A field study was established to assess the effects of a sewage sludge (SS), a mixed municipal solid waste compost (MMSWC) and a compost produced from agricultural wastes (AWC), in a Vertisol, using Lolium multiflorum L. The amendments were applied for two consecutive years: 6, 12 and 24t dry matter ha−1 for SS, and the amendment doses for MMSWC and AWC were calculated to deliver the same amount of organic matter (OM) per unit area. The amendments had significant beneficial effects on some soil properties (e.g. soil OM, NKjeldahl, extractable P and K), and on plant productivity parameters (e.g. biomass yield, chlorophyll, foliar area). For instance, soil OM increased from 0.78% to 1.71, 2.48 and 2.51%, after two consecutive years of application of 24t dry matter ha−1 of SS, MMSWC and AWC, respectively, while the plant biomass obtained increased from 7.75tha−1 to 152.41, 78.14 and 29.26tha−1, for the same amendments. On the plant, effects were more pronounced for SS than for both compost applications, a consequence of its higher capacity to provide N to the plant in a readily available form. However, after two years of application, the effects on soil properties were more noticeable for both composts, as their OM is more resistant to mineralization, which endures their beneficial effects on soil. Cadmium, Cr, Ni and Pb pseudo-total concentrations, were not affected significantly by the application of the organic wastes to soil, in all tested doses, neither their extractability by 0.01M CaCl2. On the contrary, Cu and Zn pseudo-total concentrations increased significantly in the second year of the experiment, following the application of the higher rate of MMSWC and AWC, although their extractability remained very low (<0.5% of their pseudo-total fraction). Trace elements concentrations in the aboveground plant material were lower than their maximum tolerable levels for cattle, used as an indicator of risk of their entry into the human food chain. Despite these results, it is interesting to note that the SS promoted a significant increase in the foliar concentrations of Cu, Ni and Zn that did not happen in composts application, which can be explained by the reduction of the soil pH, as a consequence of SS degradation in soil. Concluding, if this type of organic wastes were to be used in a single application, the rate could be as high as 12 or even 24tha−1, however, if they are to be applied in an annual basis, the application rates should be lowered to assure their safe application (e.g. to 6tha−1). Moreover, it is advisable to use more stable and mature organic wastes, which have longer lasting positive effects on soil characteristics.
ABSTRACT
Type II-P supernovæ (SNe), the most common core-collapse SNe type, result from the explosions of red supergiant stars. Their detection in the radio domain testifies of the presence of ...relativistic electrons, and shows that they are potentially efficient energetic particle accelerators. If hadrons can also be accelerated, these energetic particles are expected to interact with the surrounding medium to produce a gamma-ray signal even in the multi–TeV range. The intensity of this signal depends on various factors, but an essential one is the density of the circumstellar medium. Such a signal should however be limited by electron–positron pair production arising from the interaction of the gamma-ray photons with optical photons emitted by the supernova photosphere, which can potentially degrade the gamma-ray signal by over ten orders of magnitude in the first days/weeks following the explosion. We calculate the gamma-gamma opacity from a detailed modelling of the time evolution of the forward shock and supernova photosphere, taking a full account of the non-isotropy of the photon interactions. We discuss the time-dependent gamma-ray TeV emission from Type II-P SNe as a function of the stellar progenitor radius and mass-loss rate, as well as the explosion energy and mass of the ejected material. We evaluate the detectability of the SNe with the next generation of Cherenkov telescopes. We find that, while most extragalactic events may be undetectable, Type II-P SNe exploding in our Galaxy or in the Magellanic Clouds should be detected by gamma-ray observatories such as the upcoming Cherenkov Telescope Array.
Background
Relative myocardial perfusion imaging (MPI) is the standard imaging approach for the diagnosis and prognostic work-up of coronary artery disease (CAD). However, this technique may ...underestimate the extent of disease in patients with 3-vessel CAD. Positron emission tomography (PET) is also able to quantify myocardial blood flow. Rubidium-82 (
82
Rb) is a valid PET tracer alternative in centers that lack a cyclotron. The aim of this study was to assess whether assessment of myocardial flow reserve (MFR) measured with
82
Rb PET is an independent predictor of severe obstructive 3-vessel CAD.
Methods
We enrolled a cohort of 120 consecutive patients referred to a dipyridamole
82
Rb PET MPI for evaluation of ischemia neither with prior coronary artery bypass graft nor with recent percutaneous coronary intervention that also underwent coronary angiogram within 6 months of the PET study. Patients with and without 3-vessel CAD were compared.
Results
Among patients with severe 3-vessel CAD, MFR was globally reduced (<2) in 88% (22/25). On the adjusted logistic Cox model, MFR was an independent predictor of 3-vessel CAD .5 unit decrease, HR: 2.1, 95% CI (1.2-3.8);
P
= .015. The incremental value of
82
Rb MFR over the SSS was also shown by comparing the adjusted SSS models with and without
82
Rb MFR (
P
= .005).
Conclusion
82
Rb MFR is an independent predictor of 3-vessel CAD and provided added value to relative MPI. Clinical integration of this approach should be considered to enhance detection and risk assessment of patients with known or suspected CAD.
Context. Several young supernova remnants (SNRs) have recently been detected in the high-energy (HE; 0.1 < E < 100 GeV) and very-high-energy (VHE; E > 100 GeV) gamma-ray domains. As exemplified by ...RX J1713.7−3946, the nature of this emission has been hotly debated, and direct evidence for the efficient acceleration of cosmic-ray protons at the SNR shocks still remains elusive. Aims. We study the broadband gamma-ray emission from one of these young SNRs, namely RCW 86, for which several observational lines of evidence indirectly point towards the presence of accelerated hadrons. We then attempt to detect any putative hadronic signal from this SNR in the available gamma-ray data, in order to assess the level of acceleration efficiency. Methods. We analyzed more than 40 months of data acquired by the Large Area Telescope (LAT) on-board the Fermi Gamma-Ray Space Telescope in the HE domain, and gathered all of the relevant multi-wavelength (from radio to VHE gamma-rays) information about the broadband nonthermal emission from RCW 86. For this purpose, we re-analyzed the archival X-ray data from the ASCA/Gas Imaging Spectrometer (GIS), the XMM-Newton/EPIC-MOS, and the RXTE/Proportional Counter Array (PCA). Results. Beyond the expected Galactic diffuse background, no significant gamma-ray emission in the direction of RCW 86 is detected in any of the 0.1–1, 1–10 and 10–100 GeV Fermi-LAT maps. The derived HE upper limits, together with the H.E.S.S. measurements in the VHE domain, are incompatible with a standard \hbox{$E_{\rm p}^{-2}$}Ep-2 hadronic emission arising from proton-proton interactions, and can only be accommodated by a spectral index Γ ≤ 1.8, i.e. a value in-between the standard (test-particle) index and the asymptotic limit of theoretical particle spectra in the case of strongly modified shocks. In such a hadronic scenario, the total energy in accelerated particles is at the level of \hbox{$\eta_{\rm CR} = E_{{\rm CR}}/E_{{\rm SN}} \sim 0.07~d^{2}_{{\rm 2.5~kpc}}$}ηCR=ECR/ESN~0.07 d2.5 kpc2/\hbox{$\bar{n}_{{\rm cm^{-3}}}$}n̅cm-3 (with the distance d2.5 kpc ≡ d/2.5 kpc and the effective density \hbox{$\bar{n}_{{\rm cm^{-3}}}$}n̅cm-3 ≡ \hbox{$\bar{n}$}n̅/1 cm-3), and the average magnetic field must be stronger than 50 μG in order to significantly suppress any leptonic contribution. On the other hand, the interpretation of the gamma-ray emission by inverse Compton scattering of high energy electrons reproduces the multi-wavelength data using a reasonable value for the average magnetic field of 15–25 μG. In this leptonic scenario, we derive a conservative upper limit to ηCR of 0.04 d\hbox{$^{2}_{{\rm 2.5~kpc}}$}22.5 kpc/\hbox{$\bar{n}_{{\rm cm^{-3}}}$}n̅cm-3. We discuss these results in the light of existing estimates of the magnetic field strength, the effective density and the acceleration efficiency in RCW 86.
Piezoelectric converters designed for harvesting energy from mechanical vibrations have been fabricated by micromachining technologies. They are characterized by applying a sinusoidal oscillation as ...mechanical input and by using a resistive load to measure the output power of the system. A maximum output power of 40μW has been measured for a PZT based harvester excited by an input vibration having a frequency of 1.8kHz and an amplitude of 180nm. Preliminary experimental results on AlN based devices are also presented. A model capable of estimating the output power as a function of material parameters and device dimensions has been developed. Theoretical estimations have been compared with experimental results.
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