Chitosan has been shown to be a promising scaffold for various applications in tissue engineering. In this study, a chitosan-gelatin complex was fabricated as a scaffold by a freezing and lyophilizing technique. Chitosan's structure and characteristics are similar to those of glycosaminoglycan (GAG) and its analogs, and possesses various biological activities, whereas gelatin can serve as a substrate for cell adhesion, differentiation, and proliferation. With the use of autologous chondrocytes isolated from pig's auricular cartilage and seeded onto the chitosan-gelatin scaffold, elastic cartilages have been successfully engineered at the porcine abdomen subcutaneous tissue. After 16 weeks of implantation, the engineered elastic cartilages have acquired not only normal histological and biochemical, but also mechanical properties. The tissue sections of the engineered elastic cartilages showed that the chondrocytes were enclosed in the lacuna, similar to that of native cartilage. The presence of elastic fibers in the engineered cartilages was also demonstrated by Vehoeff's staining, and immunohistochemical staining confirmed the presence of type II collagen in the engineered cartilages. Quantitatively, the GAG in the engineered cartilages reached 90% of the concentration in native auricular cartilage. Furthermore, biomechanical analysis demonstrated that the extrinsic stiffness of the engineered cartilages reached 85% of the level in native auricular cartilage when it was harvested at 16 weeks. Thus, this study demonstrated that the chitosan-gelatin complex may serve as a suitable scaffold for cartilage tissue engineering.

Sr 2 RuO 4 is a leading candidate for chiral p-wave superconductivity. The detailed mechanism of superconductivity in this material is still the subject of intense investigations. Since superconductivity is sensitive to the topology of the Fermi surface (the contour of zero-energy quasi-particle excitations in the momentum space in the normal state), changing this topology can provide a strong test of theory. Recent experiments tuned the Fermi surface topology efficiently by applying planar anisotropic strain. Using functional renormalization group theory, we study the superconductivity and competing orders in Sr 2 RuO 4 under strain. We find a rapid initial increase in the superconducting transition temperature T c , which can be associated with the evolution of the Fermi surface toward a Lifshitz reconstruction under increasing strain. Before the Lifshitz reconstruction is reached, however, the system switches from the superconducting state to a spin density wave state. The theory agrees well with recent strain experiments showing an enhancement of T c followed by an intriguing sudden drop.

This paper presents the system-level and component design of a micro steam turbine power plant-on-a-chip which implements the Rankine cycle for micro power generation. The microfabricated device consists of a steam turbine that drives an integrated micropump and generator. Two-phase flow heat exchangers are also integrated on-chip with the rotating components to form a complete micro heat engine unit, converting heat to electricity. The system-level design includes cycle analysis and overall performance predictions, accounting for the expected performance of miniaturized components, thermal and structural integrity of the microsystem, and system-level trade-offs for optimal overall performance. Operating principles and design studies are also presented for the core component, with emphasis on a multistage, planar, radial microturbine and a spiral groove viscous pump. Design consideration for two-phase flow heat exchangers, microbearings, seals and micro-generators are also presented. Expected power levels range from 1–12 W per chip with energy conversion efficiency in the range of 1–11%. This suggests power density of up to 12 kW/kg for this technology, which is an order of magnitude greater than competing technologies, such as thermoelectrics. This study suggests the viability of a micro Rankine power plant-on-a-chip, but also identifies critical engineering challenges that must be met for practical implementation.

Our aim was to investigate the effect of artificial liver blood purification treatment on the survival of severe/critical patients with coronavirus disease 2019 (COVID‐19). A total of 101 severe and critical patients with coronavirus SARS‐CoV‐2 infection were enrolled in this open, case‐control, multicenter, prospective study. According to the patients’ and their families’ willingness, they were divided into two groups. One was named the treatment group, in which the patients received artificial liver therapy plus comprehensive treatment (n = 50), while the other was named the control group, in which the patients received only comprehensive treatment (n = 51). Clinical data and laboratory examinations, as well as the 28‐day mortality rate, were collected and analyzed. Baseline data comparisons on average age, sex, pre‐treatment morbidity, initial symptoms, vital signs, pneumonia severity index score, blood routine examination and biochemistry indices etc. showed no difference between the two groups. Cytokine storm was detected, with a significant increase of serum interleukin‐6 (IL‐6) level. The serum IL‐6 level decreased from 119.94 to 20.49 pg/mL in the treatment group and increased from 40.42 to 50.81 pg/mL in the control group (P < .05), indicating that artificial liver therapy significantly decreased serum IL‐6. The median duration of viral nucleic acid persistence was 19 days in the treatment group (ranging from 6 to 67 days) and 17 days in the control group (ranging from 3 to 68 days), no significant difference was observed (P = .36). As of 28‐day follow‐up,17 patients in the treatment group experienced a median weaning time of 24 days, while 11 patients in the control group experienced a median weaning time of 35 days, with no significant difference between the two groups (P = .33). The 28‐day mortality rates were 16% (8/50) in the treatment group and 50.98% (26/51) in the control group, with a significant difference (z = 3.70, P < .001). Cytokine storm is a key factor in the intensification of COVID‐19 pneumonia. The artificial liver therapy blocks the cytokine storm by clearing inflammatory mediators, thus preventing severe cases from progressing to critically ill stages and markedly reducing short‐term mortality.