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Sponges with highly absorptive properties have been widely used in emergency hemostasis. Graphene oxide (GO) has been extensively investigated in biomedical applications and is a promising candidate for hemostatic sponges. However, GO has been demonstrated to have adverse effects on the human body. To overcome this problem, a hemostatic sponge based on modified GO and carboxymethyl chitosan (CMCS) is successfully prepared, which has excellent water absorption ability and mechanical strength. Importantly, hemostasis assays showed that the composite sponge exhibited high hemostatic efficiency, and the possible hemostatic mechanism is also discussed in this study. Moreover, the results of in vitro antibacterial tests reveal that the composite sponge also presents strong antimicrobial effects against Staphylococcus aureusand Escherichia coli. Significantly, the composited sponge used as hemostatic dressing can effectively promote cell proliferation, achieving a wound closure rate of 95% on day 12. Such a graphene-based sponge with multiple advantageous features would hold broad prospects in the hemostatic field.

We analyze a class of time-triggered stochastic hybrid systems where the state-space evolves as per a linear time-invariant dynamical system. This continuous-time evolution is interspersed with two kinds of stochastic resets. The first reset occurs based on an internal timer that measures the time elapsed since it last occurred. Whenever the first reset occurs, the states-space undergoes a random jump, and the timer is reset to zero. The second reset occurs based on an arbitrary timer-depended rate, and whenever this reset fires, the state-space is changed based on a given random map. We provide exact conditions for this class of systems that lead to finite statistical moments and the corresponding exact analytical expressions for the first two moments. This framework is applied to study random fluctuations in the concentration of a protein in a growing cell. In the context of this example, the timer denotes the time elapsed since the cell was born, and the cell division event (first reset) is triggered based on a timer-dependent rate. The second reset corresponds to the protein synthesis in stochastic bursts, and finally, during cell growth, protein concentration continuously decreases due to dilution. Our analysis provides closed-form formulas for the noise in the protein concentration and leads to a striking result - for a constant (timer-independent) protein synthesis rate, the noise in the protein concentration is invariant of the noise in the cell-cycle time. Finally, we provide a rigorous framework for investigating protein noise levels for different forms of timer-dependent synthesis rates, as is the case for cell-cycle regulated genes inside the cell.

The adsorption between asphalt and aggregate surfaces is a crucial factor in the formation of the asphalt mixture structure, directly affecting the strength, stability, and aging rate of the mixture. This study aims to explore the physical-chemical bonding process between asphalt and aggregates and establish a reliable expression for asphalt adsorption on aggregate surfaces. The optimal wavelength and concentration of asphalt-toluene solutions were determined through Strategic Highway Research Program (SHRP) net adsorption tests. Then the aggregates' composition, shape, and texture properties were evaluated using a scanning electron microscope (SEM), needle-like content, and gray-level co-occurrence matrix. Finally, the impact of temperature, asphalt type, aggregate grain size, and surface texture on the adsorption evolution was studied based on the SHRP net adsorption test. Results showed significant differences in surface morphology among the four types of aggregates. Quartz exhibited the highest smoothness, while albite showed a high degree of roughness despite its complex surface morphology. Increasing temperature led to a decrease in the total adsorption capacity of the aggregates, especially for quartz and elpidite. The inflection points of the adsorption amount of calcite and albite shifted backward with 90# asphalt compared to 70# asphalt, indicating both physical and chemical adsorption. Additionally, changes in specific surface area had a more pronounced effect on the adsorption amount. The presence of a rich texture structure significantly increased the pre-sorption rate of the aggregates and ultimately influenced the adsorption amount. The research findings provide insights to more fully understand the evolution of adsorption behavior between asphalt and aggregate surfaces.