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We present a broadband Ho:CALGO regenerative amplifier operating at 2.1 μm, delivering a pulse energy of 342 μJ at 1 kHz with a spectral bandwidth of 5 nm, supporting sub-ps pulse duration.

We report on the development of 2.1-µm high-power Kerr-lens mode-locked thin-disk oscillator configurations based on Ho:YAG, reaching up to 29 W of output power and 1.74 µJ of pulse energy.

The permeability of rock fractures is a crucial parameter for flow processes in the subsurface. In the last few decades, different methods were developed to investigate on permeability in fractures, such as flow-through experiments, numerical flow simulations, or empirical equations. In recent years, the topological method of persistent homology was also used to estimate the permeability of fracture networks and porous rocks but not for rough single fractures yet. Hence, we apply persistent homology analysis on a decimetre-scale, rough sandstone bedding joint. To investigate the influence of roughness, three different data sets are created to perform the analysis: (1) 200 µm , (2) 100 µm , and (3) 50 µm resolutions. All estimated permeabilities were then compared to values derived by experimental air permeameter measurements and numerical flow simulation. The results reveal that persistent homology analysis is able to estimate the permeability of a single fracture, even if it tends to slightly overestimate permeabilities compared to conventional methods. Previous studies using porous media showed the same overestimation trend. Furthermore, the expenditure of time for persistent homology analysis, as well as air permeameter measurements and numerical flow simulation, was compared, which showed that persistent homology analysis can be also an acceptable alternative method. [ABSTRACT FROM AUTHOR]

Background: Thrombosis is a common critical complication relating to radiofrequency catheter ablation and cryoablation. There is a possibility that high‐temperature stimulation during radiofrequency ablation or low‐temperature stimulation during cryoablation may affect the coagulability of blood. In this study, we aimed to determine the impacts of transient temperature stimulations on the coagulability of whole blood and to clarify if edoxaban suppressed the hypercoagulability. Methods: Citrated blood samples were drawn from 41 healthy subjects. Some blood samples were mixed with tissue factor (TF) and several concentrations of edoxaban (50, 100, and 200 ng/mL). Blood samples were exposed to several temperature stimulations for 1 min: heat stimulation (50°C) or cryostimulation (−20°C), and compared with control (37°C). Repeated cryostimulations or sequential cryo‐ and heat stimulation were also applied. Coagulability of whole blood was measured using a dielectric blood coagulometry. As an index of coagulability, the end of acceleration time (EAT) was used. Results: Both heat‐ and cryostimulations significantly shortened the EAT compared to the control, indicating that hypercoagulability was induced by temperature stimulations. Application of TF enhanced and extended the hypercoagulability after the temperature stimulations. Sequential application of cryo‐ followed by heat stimulation further enhanced the hypercoagulability of blood. Application of edoxaban increased the EAT in a concentration‐dependent manner in control condition. Edoxaban at 100 or 200 ng/mL completely suppressed the shortening of EAT evoked by these temperature stimulations. Conclusion: Transient temperature stimulations evoked hypercoagulability regardless of cryo‐ or heat stimulation. Edoxaban with 100 ng/mL or more eliminated this temperature‐stimulated hypercoagulability. [ABSTRACT FROM AUTHOR]

The permeability of rock fractures is a crucial parameter for flow processes in the subsurface. In the last decades different methods were developed to investigate on permeability in fractures, such as flow through experiments, numerical flow simulations or empirical equations. In recent years, the topological method persistent homology was also used to estimate permeability in fracture networks and porous rocks, but not for rough single fractures. Hence, we apply persistent homology analysis on a decimeter-scale, rough sandstone bedding joint. To investigate on the influence of roughness, three different data sets are created to perform the analysis: (1) 200 μm resolution, (2) 100 μm resolution and (3) 50 μm resolution. All estimated permeabilities were then compared to values derived by experimental air permeameter measurements and numerical flow simulation. The results reveal that persistent homology analysis is able to estimate the permeability of a single fracture even if it tends to slightly overestimate permeabilities compared to conventional methods. Previous studies using porous media showed the same overestimation trend. Furthermore, expenditure of time for persistent homology analysis as well as air permeameter measurements and numerical flow simulation was compared which showed that persistent homology analysis can be also an acceptable alternative for conventional methods in this regard. [ABSTRACT FROM AUTHOR]