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The sensory qualities of brewed coffee are known to be strongly correlated with the total dissolved solids (TDS) and extraction yield (E) of the brew. Here, we derive a predictive model for the TDS and E of full immersion brewed coffee using a pseudo-equilibrium desorption approach. Assuming a single, species-averaged equilibrium constant [Formula: see text] yields theoretical predictions indicating that the TDS is approximately inversely proportional to the water/coffee mass brew ratio, while E is independent of the brew ratio. Our experimental results strongly accord with both theoretical predictions, and indicate that E is approximately 21% over a wide range of brew ratios. An analysis of the standard oven-drying method for measuring E indicates that it yields significant underestimates of the true value at equilibrium, due to retained brew within the spent moist grounds. We further demonstrate that [Formula: see text] is insensitive to grind size, roast level, and brew temperature over the range 80-99 °C. Taken together, our results indicate that full immersion brewing offers precise control over the TDS at equilibrium but little control over E, and that practitioners should pay careful attention to their brew ratio as the most important parameter for full-immersion brewing.

Electrospinning is an important technique to fabricate nanofibers. In recent years, near-field electrospinning (NFES) has been developed to enhance the control of nanofiber deposition compared to conventional electrospinning, achieved by reducing the operating distance and electric field. This enables the construction of high-aspect ratio 3D structures in a self-aligned, layer-by-layer manner. However, the alignment of fiber deposition can be hindered by charge accumulation in the polymer fibers. Furthermore, a theoretical understanding of the underlying fiber deposition mechanism is still lacking. Herein, we present a numerical model for studying the charge transport, dissipation, and accumulation of NFES polymer fiber deposition. The model reveals that the presence of a trapped state in polymeric materials imposes limitations on the quality of charged fiber deposition. Moreover, the effect of different substrate materials on charge dissipation in fiber deposition is studied. To validate the model, we compare the simulation results with NFES experiments, demonstrating qualitative agreement. We also analyze the effect of the fiber materials and experimental parameters on the printing quality. This model provides an approach to analyze and optimize the operating parameters of NFES to achieve precise and stable nanofiber deposition. [ABSTRACT FROM AUTHOR]

Additive micro/nano‐manufacturing of polymeric precursors combining with a subsequent pyrolysis step enables the design‐controlled fabrication of micro/nano‐architected 3D pyrolytic carbon structures with complex architectural details. Pyrolysis results in a significant geometrical shrinkage of the pyrolytic carbon structure, leading to a structural dimension significantly smaller than the resolution limit of the involved additive manufacturing technology. Combining with the material properties of carbon and 3D architectures, architected 3D pyrolytic carbon exhibits exceptional properties, which are significantly superior to that of bulk carbon materials. This article presents a comprehensive review of the manufacturing processes of micro/nano‐architected pyrolytic carbon materials, their properties, and corresponding demonstrated applications. Acknowledging the "young" age of the field of micro/nano‐architected carbon, this article also addresses the current challenges and paints the future research directions of this field. [ABSTRACT FROM AUTHOR]

Exploring innovative strategies for molecular structuring of dynamic materials that combine self‐correcting intrinsic reversibility with the robustness of covalent bonds, has been a long‐standing objective from applications perspective in fields ranging from molecular engineering to nanotechnology and interfacial science. To establish dynamic covalent chemistry approaches combined with interfacial polymerization, herein, a distinct synthetic approach is reported to develop disulfide‐bridged 2D polymeric C3N3S3 triazine thin‐films by interfacial thiol‐disulfide dynamic exchange process crosslinking tritopic planar 1,3,5‐triazine‐2,4,6‐trithiol molecular tectons via intermolecular disulfide formation in the presence of I2 vapors at the air/water interface under redox condition. The resulting centimeter‐scale polymeric thin‐films are covalently cross‐linked, dynamic in nature, featuring tunable thickness (6–200 nm) and significant morphological variations are realized under the influence of varying reaction time, concentration and types of reducing agents. Notably, C3N3S3 polymer thin films exhibit a transflectance of around 99.5% in the range from 430 to 1800 nm, show high refractive indices (1.730–1.488) and optical anisotropy with uniaxial negative birefringence. The C3N3S3 free‐standing polymer thin‐films can be easily transferred to different substrates or possibly into application‐relevant forms for device fabrications, making this useful from materials application perspective. [ABSTRACT FROM AUTHOR]

Introduction: The intra-aortic balloon pump (IABP) and Impella are left ventricular unloading devices with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) in place and later serve as bridging therapy when VA-ECMO is terminated. We aimed to determine the potential differences in clinical outcomes and rate of complications between the two combinations of mechanical circulatory support. Methods: This was a retrospective, single institutional cohort study conducted in the intensive care unit (ICU) of Queen Elizabeth Hospital, Hong Kong. Inclusion criteria included all patients aged ⩾18 years, who had VA-ECMO support, and who had left ventricular unloading by either IABP or Impella between January 1, 2018 and October 31, 2020. Patients <18 years old, with central VA-ECMO, who did not require left ventricular unloading, or who underwent surgical venting procedures were excluded. The primary outcome was ECMO duration. Secondary outcomes included length of stay (LOS) in the ICU, hospital LOS, mortality, and complication rate. Results: Fifty-two patients with ECMO + IABP and 14 patients with ECMO + Impella were recruited. No statistically significant difference was observed in terms of ECMO duration (2.5 vs 4.6 days, p = 0.147), ICU LOS (7.7 vs 10.8 days, p = 0.367), and hospital LOS (14.8 vs 16.5 days, p = 0.556) between the two groups. No statistically significant difference was observed in the ECMO, ICU, and hospital mortalities between the two groups. Specific complications related to the ECMO and Impella combination were also noted. Conclusions: Impella was not shown to offer a statistically significant clinical benefit compared with IABP in conjunction with ECMO. Clinicians should be aware of the specific complications of using Impella. [ABSTRACT FROM AUTHOR]

A 59-year-old female was admitted for non-ST-segment elevation myocardial infarction and Killip class 3 heart failure with a left ventricular ejection fraction of 30%. Coronary angiogram showed moderate to severe stenosis over the ostial-proximal left anterior descending artery with minor disease over the left circumflex artery and right coronary artery. We describe a complication encountered where a protruding stent was weakened and elongated during our attempts to remove it, risking possible breakage, stent embolization, and long stent protrusion inside the aorta. We then describe treatment with what we call the alpha-loop snaring technique, which, to our knowledge, is the first report describing this novel approach, which can salvage a failing snaring attempt of a completely deployed and dislodged coronary stent.