Chinese Journal of Biotechnology,Vol 34,No. 12
Genetically engineered intestinal microbes could be powerful tools for the detection and treatment of intestine inflammation due to their non-invasive character, low cost, and convenience. Intestinal inflammation is usually detected along with an increasing concentration of thiosulfate and tetrathionate molecules in the intestines. ThsSR and TtrSR are two-component biosensors to detect the presence of thiosulfate and tetrathionate molecules, respectively. In real-life intestinal inflammation detection, sophisticated instruments are needed if fluorescent proteins are used as reporters. However, chromoproteins and other colored small molecules, which can be observed by the unaided eye, could extend the use of ThsSR and TtrSR biosensors to detect intestine inflammation. The feasibility of ThsSR and TtrSR systems was tested by monitoring the fluorescence intensity of sfGFP in response to the concentrations of thiosulfate and tetrathionate, followed by the incorporation of the two systems into Escherichia coli Top10 and E. coli Nissle 1917. Considering the application in real-life, sfGFP was substituted by a series of chromoproteins and chromogenic small molecules. The potential for the real-life application of the two systems was further corroborated by substituting sfGFP with a series of chromoproteins and a protoviolaceinic acid synthesis cassette as reporter genes in E. coli Top10. The results indicated that signal expression of the new systems had a positive correlation with the concentration of tetrathionate or thiosulfate. Thus, the modified ThsSR and TtrSR systems may potentially be applied in human body for the detection of intestinal inflammation in families.
Analysis on the Steam Temperature Deviation of Water Wall and the Countermeasures of Design and Operation for a 1 000 MW Ultra Supercritical Boiler With Opposed Firing
Proceedings of the CSEE,Vol 39,No. 03
The hydrodynamic calculation and experimental study were carried out for the steam temperature deviation of water wall in the furnace of the 1 000 MW ultra supercritical boiler. Based on the boiler structure and combustion mode, a mathematical model of network system of a 1 000 MW boiler was established. According to the flow loop, the relevant test points were arranged on site. The law of the various factors on the wall temperature deviation was explored through the field test of startup of boilers, the experiment on different working ways of coal pulverizers and the mixing effect test of intermediate mixing headers, combined with the results of the hydrodynamic calculation. The results of the study indicate that the higher increase rate of boiler load and local heat load lead to large steam temperature deviation at the outlet of furnace and the increase rate of boiler load should be not more than 25 MW/min during the startup of boilers. Besides, through the experiment on different working ways of coal pulverizers, the working ways of BCEF and ABCEF coal pulverizers are recommended. It appears that the mixing headers have a good mixing effect between 50% BMCR load and 100% BMCR load in the intermediate transition section. In terms of boiler structure design, in order to improve the hydrodynamic adaptability of the front wall of the upper furnace, the flow cross-sectional area of the front wall should be increased.
Microbiology China,Vol 46,No. 09
[Background] In addition to orchid mycorrhizal fungi, the roots of orchids harbor plant fungal endophytes which are termed root-associated fungi (RAF). [Objective] RAF were screened from three endangered photosynthetic Cypripedium species distributed in coniferous forest and shrub habitats with the culture-dependent (isolations from root fragments) techniques. The species richness and the degree of RAF community differentiation of the Cypripedium species and two different habitats were determined. Ecological function analysis of RAF was also performed. [Methods] RAF were isolated from surface-sterilized root fragments of orchids. Total DNA was extracted from isolated RAF and internal transcribed spacer (ITS) was amplified. The ITS-PCR products were sequenced. Phylogenetic analysis was applied. Species richness and diversity of fungal communities of studied orchid species and collecting sites were estimated. After the alignment of the ITS sequences of RAF in NCBI database, the annotation of the closest matched sequences was used to analyze the ecological function. [Results] A total of 278 RAF isolates, corresponding to 25 operational taxonomic units (OTUs), were identified, including 23 Ascomycota OTUs and 2 Mucoromycota OTUs. The RAF species richness of Cypripediumtibeticum was higher than that of C. flavum. The degree of RAF community differentiation of different Cypripedium species was higher than that of different habitats. Fungal taxa in the roots of the three Cypripedium species showed that they were assigned to three trophic modes of symbiotroph, saprotroph, and pathotroph, respectively, and eight guilds, which were ectomycorrhizal, plant pathogen, endophyte, animal pathogen, fungal parasite, ericoid mycorrhizal, undefined saprotroph and uncertain, respectively. [Conclusion] This study revealed the distribution characteristics and ecological function of RAF in roots of three Cypripedium species sampled from two different habitats, and also laid a foundation for the symbiotic relationship study of RAF and Cypripedium species in the future.
Chinese Journal of Energetic Materials,Vol 27,No. 05
To investigate the thermal safety of modular charge, based on the chemical reaction mechanism of combustible cartridge materials and single-base propellants, we established a two-dimensional unsteady state cook-off model of modular charges. The fast cook-off response characteristics of modular charge were analyzed at the external heating rates of 1–10 K·min −1. The results show that the initial ignition position of modular charges is all in the single-base propellant on the left and right sides near the inner wall surface of combustible cartridge materials, and the ignition zones are two circular response zones. With the heating rate increasing, the circular response zone will move from the inside of the single-base propellant to the inner wall of combustible cartridge material, but the change in external heating rates has little effect on the ignition position of modular charge. At the heating rates of 1, 6 and 10 K·min −1, the temperatures occurring the cook-off response of single-base propellant are 458.2, 453.9 and 455.7 K, respectively, which are basically consistent with the ignition temperatures (443–463 K) measured by experiments. The change in the external heating rate has little effect on the ignition temperature occurring the cook-off response of modular charge, but the ignition time occurring the cook-off response of modular charge reveals an exponential decay with the heating rate increasing.
Operations Research and Management Science,Vol 28,No. 06
Information asymmetry widely exists in the process of confirming storage financing. This paper depicts the relationship of the financing system members by the Stackelberg game model and uses dynamic programming and other optimization methods to solve the corresponding equilibrium decision. Three situations of demand information asymmetry—information fraud, information superiority, and information hiding are summarized. We also analyze the impact of different cases of information asymmetry on the financing system and further put forward the screening contract mechanism to achieve the information screening. The results show that retailers can get high advantage from the information asymmetry, which also brings damage to the other financing participants. Information hiding brings bigger damage to the manufacturer. The two-part tariff contract can realize information screening, but the manufacturer has to pay information rent for it, which causes efficiency loss of the financing system. The two-part tariff with the repurchase mechanism under the reasonable parameter setting helps to further improve the interest of the financing system. It can even reach the secondary coordination state and realize the Pareto improvement of the financing system members. This paper provides the theoretical reference and decision basis for controlling information risk and improving financing efficiency of the supply chain finance.