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Arming at the coexistence dilemma of inventory overhang and shortage of different maintenance equipment supply nodes, a steady-state coefficient of a supply node has been described with which contains inventory level, the support degree between nodes each other, the demand status of the area guaranteed by the node and the cost of risk when the demand cannot be met. The steady-state coefficient of the inventory network was calculated on the base of all of support nodes. The active adjustment is carried out flowing the corresponding algorithm according to the gap between the steady-state coefficient and the threshold which has been set before. The scientific, automatic and intelligent level of equipment adjustment can be greatly improved, consequently the success rate of maintenance support is improved if the passive stock adjustment is combined because of out of stock at the same time.

The oxygen regulator is the core component of the aircraft life support system, which adjusts the flow and pressure of the breathing gas according to the pilot's breathing needs. In response to the problem that structural parameters are difficult to adjust and prone to jitter when the indirect oxygen regulator system is stable, a direct oxygen regulator is designed using a stepper motor to drive a lung-type flapper, replacing the diaphragm lever-type structure of the indirect oxygen regulator. Due to the nonlinearity and time-varying nature of the dynamic characteristics of oxygen regulators, a single-neuron PID control strategy based on online identification of RBF neural networks is proposed to improve the PID control performance. The RBF neural network is used to identify the Jacobian information of the controlled object, and the single-neuron PID controller completes the online adjustment of the controller parameters to realize the intelligent control of the system. Simulation experimental studies are conducted to verify the performance of the direct oxygen regulator. The result analysis verifies the excellence of the single-neuron PID control strategy based on online recognition of the RBF neural network to improve the system performance. [ABSTRACT FROM AUTHOR]

Despite decades of studies meant to analyse the bacterial response to carbon limitation, we still miss a high-resolution overview of the situation. All gene expression changes observed in such conditions cannot solely be accounted for by the global regulator Crp either free or bound to its effector, cyclic AMP. Here, for the first time, we evaluated the response of both CDS (protein-coding sequence) and ncRNA (non-coding RNA) genes to carbon limitation, revealed cellular functions of differentially expressed genes systematically, quantified the contribution of Crp-cAMP and other factors to regulation and deciphered regulation strategies at a genomewide scale. Approximately one-third of the differentially expressed genes we identified responded to Crp-cAMP via its direct or indirect control, while the remaining genes were subject to growth rate-dependent control or were controlled by other regulators, especially RpoS. Importantly, gene regulation mechanisms can be established by expression pattern studies. Here, we propose a comprehensive picture of how cells respond to carbon scarcity. The global regulation strategies thus exposed illustrate that the response of cell to carbon scarcity is not limited to maintaining sufficient carbon metabolism via cAMP signalling while the main response is to adjust metabolism to cope with a slow growth rate., (© 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Bone tissue engineering through seeding of stem cells in three-dimensional scaffolds has greatly improved bone regeneration technology, which historically has been a constant challenge. In this study, we researched the use of adipose-derived stem cell (ADSC)-laden layer-by-layer paper-stacking polycaprolactone/gelatin electrospinning nanofibrous membranes for bone regeneration. Using this novel paper-stacking method makes oxygen distribution, nutrition, and waste transportation work more efficiently. ADSCs can also secrete multiple growth factors required for osteogenesis. After the characterization of ADSC surface markers CD29, CD90, and CD49d using flow cytometry, we seeded ADSCs on the membranes and found cells differentiated, with significant expression of the osteogenic-related proteins osteopontin, osteocalcin, and osteoprotegerin. During 4 weeks in vitro, the ADSCs cultured on the paper-stacking membranes in the osteogenic medium exhibited the highest osteogenic-related gene expressions. In vivo, the paper-stacking scaffolds were implanted into the rat calvarial defects (5 mm diameter, one defect per parietal bone) for 12 weeks. Investigating with microcomputer tomography, the ADSC-laden paper-stacking membranes showed the most significant bone reconstruction, and from a morphological perspective, this group occupied 90% of the surface area of the defect, produced the highest bone regeneration volume, and showed the highest bone mineral density of 823.06 mg/cm(3). From hematoxylin and eosin and Masson staining, the new bone tissue was most evident in the ADSC-laden scaffold group. Using quantitative polymerase chain reaction analysis from collected tissues, we found that the ADSC-laden paper-stacking membrane group presented the highest osteogenic-related gene expressions of osteocalcin, osteopontin, osteoprotegerin, bone sialoprotein, runt-related transcription factor 2, and osterix (two to three times higher than the control group, and 1.5 times higher than the paper-stacking membrane group in all the genes). It is proposed that ADSC-laden layer-by-layer paper-stacking scaffolds could be used as a way of promoting bone defect treatment.

Objective: To explore the role of ompT gene in uropathogenic E. coli (UPEC) CFT073 strain in urinary tract infection (UTI)., Methods: An ompT deletion mutant (COTD) was generated by λ Red recombineering in the UPEC CFT073 strain, which was characterized by PCR and sequencing. C57B/L6 mouse models of acute UTI with the mutant and wild-type strains were established to compare the colonization abilities of the two strains in the bladder. The adhesion of CFT073 mutant to human unthelial 5637 cells was also investigated in vitro., Results: PCR and DNA sequencing confirmed the loss of ompT gene in the mutant COTD. The in vitro adhesion rate of the mutant strain COTD to 5637 cells was (6.7±2.2)%, significantly lower than that of (8.3±1.9)% of the wild-type strain (P<0.05). In the murine models of acute UTI, the mutant strain showed a mean colonization number of about (17±8)×10⁴ cfu, which was significantly lower than that of (7∓2)×10⁵ cfu of the wide-type CFT073 strain (P<0.05)., Conclusion: OmpT gene can be involved in the colonization of UPEC in the bladder tissue and plays an important role in the pathogenesis of UPEC-induced UTI.