Detection of Electromagnetic Seismic Precursors from Swarm Data by Enhanced Martingale Analytics.

The detection of seismic activity precursors as part of an alarm system will provide opportunities for minimization of the social and economic impact caused by earthquakes. It has long been envisaged, and a growing body of empirical evidence suggests that the Earth's electromagnetic field could contain precursors to seismic events. The ability to capture and monitor electromagnetic field activity has increased in the past years as more sensors and methodologies emerge. Missions such as Swarm have enabled researchers to access near-continuous observations of electromagnetic activity at second intervals, allowing for more detailed studies on weather and earthquakes. In this paper, we present an approach designed to detect anomalies in electromagnetic field data from Swarm satellites. This works towards developing a continuous and effective monitoring system of seismic activities based on SWARM measurements. We develop an enhanced form of a probabilistic model based on the Martingale theories that allow for testing the null hypothesis to indicate abnormal changes in electromagnetic field activity. We evaluate this enhanced approach in two experiments. Firstly, we perform a quantitative comparison on well-understood and popular benchmark datasets alongside the conventional approach. We find that the enhanced version produces more accurate anomaly detection overall. Secondly, we use three case studies of seismic activity (namely, earthquakes in Mexico, Greece, and Croatia) to assess our approach and the results show that our method can detect anomalous phenomena in the electromagnetic data.

Topology of ferroelectric nematic droplets: the case driven by flexoelectricity or depolarization field.

The recent discovery of ferroelectric nematics provides new opportunities for exploring polar topology in liquid matter. Here, we report numerous potential polarization topological states (e.g., polar vortex-like and line disclination mediated structures) in confined ferroelectric nematics with similar free-energy levels. In the experiment, they appear according to the confinement size and surface anchoring conditions. Based on a minimal analytical approach, we reveal that the topological transformation is balanced among the nematic elasticity, the polarization gradient, the flexoelectric and the depolarization interactions.

Response of helielectric nematics under an in-plane electric field.

In traditional chiral nematic liquid crystals, the apolar cholesterics, the dielectric effect is the main driving force for responding to an electric field. The emerging polar chiral nematics, dubbed helielectric nematics, are the polar counterparts of the cholesterics. The head-to-tail symmetry breaking of the new matter state enables it to respond sensitively to the polarity of an electric field. Here, we report on the observation of a sequential polar winding/unwinding process of polarization helices under an electric field applied perpendicular to the helical axes, which behaves distinctly from the unwinding of the apolar cholesteric helices. Understanding the helix-unwinding behaviors provides insights for developing switchable devices based on helielectric nematics.

A novel seawater hydrothermal-deep eutectic solvent pretreatment enhances the production of fermentable sugars and tailored lignin nanospheres from Pinus massoniana.

Lignocellulose biorefinery depended on effective pretreatment strategies is of great significance for solving the current global crisis of ecosystem and energy security. This study proposes a novel approach combining seawater hydrothermal pretreatment (SHP) and microwave-assisted deep eutectic solvent (MD) pretreatment to achieve an effective fractionation of Pinus massoniana into high value-added products. The results indicated that complex ions (Mg2+, Ca2+, and Cl-) in natural seawater served as Lewis acids and dramatically promoted the depolymerization of mannose and xylan into oligosaccharides with 40.17 % and 75.43 % yields, respectively. Subsequent MD treatment realized a rapid and effective lignin fractionation (~90 %) while retaining cellulose. As a result, the integrated pretreatment yielded ~85 % of enzymatic glucose, indicating an eightfold increase compared with untreated pine. Because of the increased hydrophobicity induced by the formation of acyl groups during MD treatment, uniform lignin nanospheres were successfully recovered from the DES. It exhibited low dispersibility (PDI = 2.23), small molecular weight (1889 g/mol), and excellent oxidation resistance (RSI = 5.94), demonstrating promising applications in functional materials. The mechanism of lignin depolymerization was comprehensively elucidated via FTIR, 2D-HSQC NMR, and GPC analyses. Overall, this study provides a novel and environmentally friendly strategy for lignocellulose biorefinery and lignin valorization.

Self-assembled soft alloy with Frank-Kasper phases beyond metals.

Soft building blocks, such as micelles, cells or soap bubbles, tend to adopt near-spherical geometry when densely packed together. As a result, their packing structures do not extend beyond those discovered in metallic glasses, quasicrystals and crystals. Here we report the emergence of two Frank-Kasper phases from the self-assembly of five-fold symmetric molecular pentagons. The µ phase, an important intermediate in superalloys, is indexed in soft matter, whereas the ϕ phase exhibits a structure distinct from known Frank-Kasper phases in metallic systems. We find a broad size and shape distribution of self-assembled mesoatoms formed by molecular pentagons while approaching equilibrium that contribute to the unique packing structures. This work provides insight into the manipulation of soft building blocks that deviate from the typical spherical geometry and opens avenues for the fabrication of 'soft alloy' structures that were previously unattainable in metal alloys.

Insights into the poplar cell wall deconstruction following deep eutectic solvent pretreatment for enhanced enzymatic saccharification and lignin valorization.

In this study, a combination of microcosmic and chemical analysis methods was used to investigate deep eutectic solvent (DES) pretreatment effects on cell wall's micromorphology and lignin's dissolution regular, in order to achieve high-performance biorefinery. The atomic force microscope observed that DES pretreatment peeled off non-cellulose components to reduced "anti-degradation barrier", resulting to improve the enzymatic saccharification from 12.36 % to 90.56 %. In addition, DES pretreatment can break the ß-O-4 bond between the lignin units resulting in a decline in molecular weight from 3187 g/mol to 1112 g/mol (0-6 h). However, long pretreatment time resulted regenerated lignin samples repolymerization. Finally, DES has good recoverability which showed saccharification still can reach 51.51 % at 6 h following four recycling rounds and regenerated lignin also had a typical and well-preserved structure. In general, this work offers important information for industrial biorefinery technologies and lignin valorization.

Analysis of 24-hour Death Risk Factors in Circulatory Failure Patients Treated with Venoarterial Extracorporeal Membrane Oxygenation

ABSTRACT Objective: To explore the factors affecting short-term prognosis of circulatory failure patients undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO) treatment. Methods: A total of 136 patients undergoing VA-ECMO were enrolled in this study and subsequently divided into the death group (n=35) and the survival group (n=101) based on whether death occurred during hospitalisation. Extracorporeal membrane oxygenation (ECMO) running time, length of intensive care unit stay, length of hospital stay, costs, and ECMO complications were then compared between the two groups. Results: The average age of all patients undergoing ECMO was 47.64±16.78 years (53.2±16.20 years in the death group and 45.713±16.62 years in the survival group) (P=0.022). Patients in the survival group exhibited a clear downward trend in lactic acid value following ECMO treatment compared to those in the death group. Total hospitalisation stay was longer in the survival group (35 days) than in the death group (15.5 days) (P<0.001). In the analysis of ECMO complications, the incidence of neurological complications, renal failure, limb complications, and infection were higher in the death group than in the survival group (P<0.05 for all). Specifically, as a risk factor for patient survival and discharge, the occurrence of infection will lead to increased hospitalisation stays and costs (P<0.05 for both). Conclusion: Complications such as kidney failure and infection are associated with in-hospital death, and ECMO-related complications should be actively prevented to improve the survival rate of VA-ECMO treatment.