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Ca2+ sparks of membrane-permeabilized rat muscle cells were analyzed to derive properties of their sources. Most events identified in longitudinal confocal line scans looked like sparks, but 23% (1,000 out of 4,300) were followed by long-lasting embers. Some were preceded by embers, and 48 were “lone embers.” Average spatial width was ∼2 μm in the rat and 1.5 μm in frog events in analogous solutions. Amplitudes were 33% smaller and rise times 50% greater in the rat. Differences were highly significant. The greater spatial width was not a consequence of greater open time of the rat source, and was greatest at the shortest rise times, suggesting a wider Ca2+ source. In the rat, but not the frog, spark width was greater in scans transversal to the fiber axis. These features suggested that rat spark sources were elongated transversally. Ca2+ release was calculated in averages of sparks with long embers. Release current during the averaged ember started at 3 or 7 pA (depending on assumptions), whereas in lone embers it was 0.7 or 1.3 pA, which suggests that embers that trail sparks start with five open channels. Analysis of a spark with leading ember yielded a current ratio ranging from 37 to 160 in spark and ember, as if 37–160 channels opened in the spark. In simulations, 25–60 pA of Ca2+ current exiting a point source was required to reproduce frog sparks. 130 pA, exiting a cylindric source of 3 μm, qualitatively reproduced rat sparks. In conclusion, sparks of rat muscle require a greater current than frog sparks, exiting a source elongated transversally to the fiber axis, constituted by 35–260 channels. Not infrequently, a few of those remain open and produce the trailing ember.

This paper describes the modification of nonwoven fabric such that it responds by releasing an encapsulated antimicrobial from within an attached vesicle in response to two species of pathogenic bacteria (Staphylococcus aureus MSSA 476 and Pseudomonas aeruginosa PAO1), but does not respond to nonpathogenic Escherichia coli DH5alpha. This concept is based on the generalization that a majority of pathogenic bacteria secrete virulence factors such as toxins and lipases that actively damage cell membranes, typically observed as tissue damage around infected wounds, while nonpathogenic bacteria do not (or not at high concentration). The eventual aim of this work is to produce responsive dressings which release antimicrobials and change color only on infected wounds. This paper details preliminary approaches to achieving this goal, including vesicle-bacteria studies in aqueous suspension, and fluorescence imaging of fluorescein containing vesicles lysed by S. aureus and P. aeruginosa, but not by E. coli.

Torrefaction is a slow pyrolysis process that is carried out in the relatively low temperature range of 220-300°C. The influence of torrefaction as a pretreatment on biomass gasification technology was investigated using a bench-scale torrefaction unit, a bench-scale laminar entrained-flow gasifier, and the analysis techniques TGA-FTIR and low temperature nitrogen adsorption. A series of experiments were performed to examine the characteristics of the torrefaction process, the properties of torrefaction products, and the effects of torrefaction on gas composition, cold gas efficiency and gasification efficiency. The results showed that during the torrefaction process the moisture content of biomass were reduced, and the wood fiber structure of the material was destroyed. This was beneficial to storage, transport and subsequent treatments of biomass in large scale. For solid products, torrefaction increased the energy density, decreased the oxygen/carbon ratio, and created a more complex pore structure. These improved the syngas quality and cold gas efficiency. Combustible gases accounted for about 50% of non-condensable gaseous torrefaction products. Effective use of the torrefaction gases can save energy and improve efficiency. Overall, biomass torrefaction technology has good application prospects in gasification processes. Energy is the most important basis for economic and social development. With large-scale industrial development, the total exploitable amount of fossil fuel is declining, and environmental pollution is increasing. With the advantages of being clean and CO 2 neutral, biomass is the only renewable energy source that can fix carbon, and biomass has gradually won worldwide attention. However, as a result of its dispersion, low energy density, low bulk density and high moisture content, the costs of logistics and transport are increased. Those factors make large-scale utilization of biomass for bioenergy production inefficient and uneconomic. Consequently, it is necessary to enhance the characteristics of biomass feedstocks through pretreatment.At present, biomass pretreatments include drying, pelletisation, pyrolysis and torrefaction. While drying is a relatively *Corresponding author (email: zhoujs@cmee.zju.edu.cn) mature conventional technology, the moisture content of biomass is as high as typically about 10 wt% after drying [1]. Dried biomass will re-absorb water and start to decompose. In addition, drying has little benefit for the improvement on the properties such as low energy density and bulk density, high oxygen content and grindability. As a slow pyrolysis process at moderate temperatures under atmospheric pressure, torrefaction can solve these problems. Using torrefaction technology, the energy density and bulk density of biomass are increased, and the costs of transportation and storage reduced. Moreover, because of its high process efficiency (94%) compared with pelletisation (84%) and pyrolysis (64%), torrefaction is potentially the best method for improving the economics of the ...

Wound dressings that can simultaneously treat bacterial infections and various bleeding complications are highly desirable in clinics. Moreover, multidrug‐resistant (MDR) bacterial infection has posed another great challenge for clinical wound care, as there are fewer effective antimicrobial agents available for killing these bacteria. To meet the clinical need, serials of polysaccharide‐peptide cryogels have been developed with excellent antibacterial efficacy and hemostatic property. With glycol chitosan (GC) and ε‐poly lysine (EPL) as the major components, the cryogels yield significantly lower amounts of blood loss compared with commercially available hemostatic dressings. The incorporation of EPL significantly enhances the antibacterial activity including killing MDR bacteria capacity and prevents the bacterial infection of skin wounds. The cryogel treated wounds demonstrate significantly higher healing efficiency compared to the controlled MDR bacteria infected wounds. The GC‐EPL polysaccharide‐peptide cryogels may become competitive multifunctional wound dressings for bleeding control and bacteria‐infected wound healing.