Quantum superposition of thermodynamic evolutions with opposing time’s arrows

Microscopic physical laws are time-symmetric, hence, a priori there exists no preferential temporal direction. However, the second law of thermodynamics allows one to associate the “forward” temporal direction to a positive variation of the total entropy produced in a thermodynamic process, and a negative variation with its “time-reversal” counterpart. This definition of a temporal axis is normally considered to apply in both classical and quantum contexts. Yet, quantum physics admits also superpositions between forward and time-reversal processes, whereby the thermodynamic arrow of time becomes quantum-mechanically undefined. In this work, we demonstrate that a definite thermodynamic time’s arrow can be restored by a quantum measurement of entropy production, which effectively projects such superpositions onto the forward (time-reversal) time-direction when large positive (negative) values are measured. Finally, for small values (of the order of plus or minus one), the amplitudes of forward and time-reversal processes can interfere, giving rise to entropy-production distributions featuring a more or less reversible process than either of the two components individually, or any classical mixture thereof.

Terlipressin for Hepatorenal Syndrome-Acute Kidney Injury in Acute-On-Chronic Liver Failure: A Single-Center Retrospective Cohort Study

Objectives: Patients with hepatorenal syndrome-acute kidney injury (HRS-AKI) based on acute-on-chronic liver failure (ACLF) have a high rate of mortality. Terlipressin combined with albumin is the first line therapy for HRS-AKI in cirrhosis, however, whether it is more effective than albumin alone in ACLF is unclear. We aimed to analyze therapeutic effects of terlipressin in these patients. Methods: A retrospective study was conducted on patients with HRS-AKI based on ACLF at Beijing You’an Hospital between October 2010 and October 2019. The primary endpoint was a reversal rate of HRS-AKI, which was defined as serum creatinine (sCr) reduced to within 0.3 mg/dL of baseline. The secondary endpoints included a reversal rate of HRS in patients with sCr<1.5mg/dL and 28-day survival. Results: 221 of 755 patients meet inclusion criteria. 113 cases were treated with terlipressin plus albumin (TA group), whereas 108 cases with albumin alone (AA group). The reversal rate of HRS-AKI in TA group was higher compared to in AA group (35.39% vs 23.15%, P = 0.046). Additionally, reversal time in TA group was 8.18 ± 4.39 days, compared to 11.29 ± 3.67 days in AA group ( P = 0.005). In patients with sCr < 1.5mg/dL, reversal rate of HRS-AKI in TA group was 41.46% (17/47) compared to 19.61% (10/51) in AA group (P = 0.067). Furthermore, reversal time in TA group was 8.12±5.75 days, compared to 9.40±2.67 days in AA group (P=0.117). Notably, 28-day overall survival and transplantation-free survival in TA group was better than AA group (P < 0.001).Conclusions: Terlipressin combined albumin was effective for HRS-AKI in ACLF. Combination therapy tends to be more beneficial for patients with sCr level <1.5 mg/dL.

Coating Effect on the 1H—NMR Relaxation Properties of Iron Oxide Magnetic Nanoparticles

We present a 1H Nuclear Magnetic Resonance (NMR) relaxometry experimental investigation of two series of magnetic nanoparticles, constituted of a maghemite core with a mean diameter dTEM = 17 ± 2.5 nm and 8 ± 0.4 nm, respectively, and coated with four different negative polyelectrolytes. A full structural, morpho-dimensional and magnetic characterization was performed by means of Transmission Electron Microscopy, Atomic Force Microscopy and DC magnetometry. The magnetization curves showed that the investigated nanoparticles displayed a different approach to the saturation depending on the coatings, the less steep ones being those of the two samples coated with P(MAA-stat-MAPEG), suggesting the possibility of slightly different local magnetic disorders induced by the presence of the various polyelectrolytes on the particles’ surface. For each series, 1H NMR relaxivities were found to depend very slightly on the surface coating. We observed a higher transverse nuclear relaxivity, r2, at all investigated frequencies (10 kHz ≤ νL ≤ 60 MHz) for the larger diameter series, and a very different frequency behavior for the longitudinal nuclear relaxivity, r1, between the two series. In particular, the first one (dTEM = 17 nm) displayed an anomalous increase of r1 toward the lowest frequencies, possibly due to high magnetic anisotropy together with spin disorder effects. The other series (dTEM = 8 nm) displayed a r1 vs. νL behavior that can be described by the Roch’s heuristic model. The fitting procedure provided the distance of the minimum approach and the value of the Néel reversal time (τ ≈ 3.5 ÷ 3.9·10−9 s) at room temperature, confirming the superparamagnetic nature of these compounds.

Indo-Atlantic plate accelerations around the Cretaceous-Paleogene boundary: A time-scale error, not a plume-push signal

It has been suggested that plume arrival at the base of the lithosphere introduces a push force that overwhelms the balance of torques driving plate circuits, leading to plate-tectonic reorganizations. Among the most compelling evidence in support of a “plume-push” mechanism is the apparent coincidence between eruption of the Deccan flood basalts around 67–64 Ma and a short-lived increase in Indian (and decrease in African) plate speed. Using existing and newly calculated high-resolution plate-motion models, we show that plate divergence rates briefly increased throughout the Indo-Atlantic circuit, contrary to the expected effects of plume-push. We propose that this circuit-wide spike in divergence rates is best explained as the artifact of a magnetic reversal time-scale error around the much studied Cretaceous-Tertiary boundary, and that the period spanning chrons C29–C28 lasted 70% longer than currently assumed. Corrected for this error, the residual long-term patterns of Indo-Atlantic plate motions and accompanying plate-tectonic reorganization are explicable in terms of maturation of the circuit’s spreading ridges, without invoking a significant plume-push force.

The study of transcarotid artery revascularization under local versus general anesthesia with results from the Society for Vascular Surgery Vascular Quality Initiative

Objective The primary purpose of this study was to examine any potential difference in clinical outcomes between transcarotid artery revascularization performed under local anesthesia compared with general anesthesia by utilizing a large national database. Methods The primary outcome of the study was a composite endpoint of postoperative in-hospital stroke, myocardial infarction and mortality following transcarotid artery revascularization for the index procedure. Secondary outcomes included a composite outcome of postoperative in-hospital stroke, transient ischemic attack, myocardial infarction and mortality along with several subsets of its components and each individual component, flow reversal time (min), radiation dose (GY/cm2), contrast volume utilized (mL), total procedure time (min), extended total length of stay (>1 day) and extended postoperative length of stay (>1 day). Statistical analyses employed both descriptive measures to characterize the study population and analytic measures such as multivariable mixed-effect linear and logistic regressions using both unmatched and propensity-score matched cohorts. Results A total of 2609 patients undergoing transcarotid artery revascularization between the years 2016 and 2018 in the US were identified, with 82.3% performed under general anesthesia and 17.7% under local anesthesia. The primary composite outcome was observed in 2.3% of general anesthesia patients versus 2.6% of local anesthesia patients ( p = 0.808). The rate of postoperative transient ischemic attack and/or myocardial infarction was 1.6% with general anesthesia versus 1.1% with local anesthesia ( p = 0.511). For adjusted regression analysis, general anesthesia and local anesthesia were comparable in terms of primary outcome (OR: 0.72; 95% CI: 0.27–1.93, p = 0.515). As for the secondary outcomes, no significant differences were found except for contrast, where the results demonstrated significantly less need for contrast with procedures performed under general anesthesia (coefficient: 4.94; 95% CI: 1.34–8.54, p = 0.007). A trend towards significance was observed for lower rate of postoperative transient ischemic attack and/or myocardial infarction (OR: 0.33; 95% CI: 0.09–1.18, p = 0.088) and lower flow reversal time under local anesthesia (coefficient: –0.94: 95% CI: –2.1–0.22, p = 0.111). Conclusions Excellent outcomes from transcarotid artery revascularization for carotid stenosis were observed in the VQI database between the years 2016 and 2018, under both local anesthesia and general anesthesia. The data demonstrate the choice of anesthesia for transcarotid artery revascularization does not appear to have any effect on clinical outcomes. Surgical teams should perform transcarotid artery revascularization under the anesthesia type they are most comfortable with.

A micromagnetic study: lateral size dependence of the macroscopic properties of rectangular parallelepiped Cobalt-ferrite nanoferromagnetic

<span lang="EN-US">The purpose of this study is to provide systematic information through micromagnetic simulations related to the impact of particle size on the magnetic characteristics of Cobalt-ferrite MNP. The micromagnetic computations performed were based on LLG equation. The MNPs sample was simulated in the form of a rectangular parallelepiped with a thickness of 20 nm and square surface with lateral length varies from 10 to 80 nm at an interval of 10 nm. </span><span lang="EN-ID">The results of this study indicate that the size changes in Cobalt-ferrite MNP have a significant impact on various magnetic properties, such as the magnitude of the barrier energy, coercive and nucleation fields, magnetization rate, magnetization curve profile, and magnetization mode.</span><span lang="EN-ID">Cobalt-ferrite MNP with a size of 10 nm shows a single domain with a relatively short magnetization reversal time and high coercive field.</span>

Sugammadex Versus Neostigmine After Rocuronium Continuous Infusion in Patients Undergoing Liver Transplantation.

Background: Rapid neuromuscular block reversal at the end of major abdominal surgery is recommended to avoid any postoperative residual block. To date, no study has evaluated sugammadex performance after rocuronium administration in patients undergoing liver transplantation.This is a randomized controlled trial with the primary objective of assessing the neuromuscular transmission recovery time obtained with sugammadex versus neostigmine after rocuronium induced neuromuscular blockade in patients undergoing orthotopic liver transplantation.Methods: The TOF-Watch SX®, calibrated and linked to a portable computer equipped with TOF-Watch SX Monitor Software®, was used to monitor and record intraoperative neuromuscular block maintained with a continuous infusion of rocuronium. Anaesthetic management was standardized as per our institution's internal protocol. At the end of surgery, neuromuscular moderate block reversal was obtained by administration of 2 mg/kg of sugammadex or 50 mcg/kg of neostigmine (plus 10 mcg/kg of atropine). Results: Data from 41 patients undergoing liver transplantation were analysed. In this population, recovery from neuromuscular block was faster following sugammadex administration than neostigmine administration, with mean times±SD of 9.4±4.6 min and 34.6±24.9 min, respectively (p<0.0001). Conclusion: Sugammadex is able to reverse neuromuscular block maintained by rocuronium continuous infusion in patients undergoing liver transplantation. The mean reversal time obtained with sugammadex was significantly faster than that for neostigmine. It is important to note that the sugammadex recovery time in this population was found to be considerably longer than in other surgical settings, and should be considered in clinical practice.Trial registration: ClinicalTrials.gov NCT02697929 (registered 3rd March 2016).