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Platelets, small hemostatic blood cells, are derived from megakaryocytes. Both bone marrow and lung are principal sites of thrombopoiesis although underlying mechanisms remain unclear. Outside the body, however, our ability to generate large number of functional platelets is poor. Here we show that perfusion of megakaryocytes ex vivo through the mouse lung vasculature generates substantial platelet numbers, up to 3000 per megakaryocyte. Despite their large size, megakaryocytes are able repeatedly to passage through the lung vasculature, leading to enucleation and subsequent platelet generation intravascularly. Using ex vivo lung and an in vitro microfluidic chamber we determine how oxygenation, ventilation, healthy pulmonary endothelium and the microvascular structure support thrombopoiesis. We also show a critical role for the actin regulator Tropomyosin 4 in the final steps of platelet formation in lung vasculature. This work reveals the mechanisms of thrombopoiesis in lung vasculature and informs approaches to large-scale generation of platelets.

Cronobacter spp. are associated with serious infections in neonates with the clinical presentations of necrotizing enterocolitis, bacteraemia and meningitis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify 203 Cronobacter isolates from imported food during 2006-2015 with an optimized in-house database. The isolates were predominantly C. sakazakii (88.18%), followed by C. malonaticus (8.37%), C. muytjensii (1.48%), C. turicensis (0.99%) and C. dublinensis (0.99%). The result was totally consistent with that of fusA allele sequencing. 12.32% (25/203) of isolates gave inconsistent spectra following separate protein extractions. Sixty C. sakazakii isolates and 24 isolates from the other four species were chosen for multi-locus sequence type analyses (MLST) and PCR-serotyping. Thirty-one sequence types were identified. The common sequence types were ST1 (19/60) and ST4 (13/60) for C. sakazakii and ST7 (12/17) for C. malonaticus. The primary serotypes were Csak O:1 (30/60), Csak O:2 (25/60) and Cmal O:2 (16/17) for C. sakazakii and C. malonaticus isolates, respectively. In conclusion, appropriate in-house database could make MALDI-TOF MS method identifying Cronobacter spp. isolates to the species level. But the spectra data were not sufficiently consistent for subtyping, unlike MLST. The Cronobacter spp. isolates have a high diversity including recognized pathovars.

Rapid and precise identification of Cronobacter species is important for foodborne pathogen detection, however, commercial biochemical methods can only identify Cronobacter strains to genus level in most cases. To evaluate the power of mass spectrometry based on matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS) for Cronobacter species identification, 51 Cronobacter strains (eight reference and 43 wild strains) were identified by both MALDI-TOF MS and 16S rRNA gene sequencing. Biotyper RTC provided by Bruker identified all eight reference and 43 wild strains as Cronobacter species, which demonstrated the power of MALDI-TOF MS to identify Cronobacter strains to genus level. However, using the Bruker's database (6903 main spectra products) and Biotyper software, the MALDI-TOF MS analysis could not identify the investigated strains to species level. When MALDI-TOF MS analysis was performed using the combined in-house Cronobacter database and Bruker's database, bin setting, and unweighted pair group method with arithmetic mean (UPGMA) clustering, all the 51 strains were clearly identified into six Cronobacter species and the identification accuracy increased from 60% to 100%. We demonstrated that MALDI-TOF MS was reliable and easy-to-use for Cronobacter species identification and highlighted the importance of establishing a reliable database and improving the current data analysis methods by integrating the bin setting and UPGMA clustering.

Centrin self-assembly is primarily involved in fiber contraction, which is associated with the cell division cycle and ciliogenesis. During centriole separation, centrin reversible phosphorylation plays a key role. There is a question as to how centrin phosphorylation cooperatively co-exists with self-assembly during cell mitosis. Our results suggested that centrin from Euplotes octocarinatus (EoCen) in the self-assembly state can also be phosphorylated by protein kinase A (PKA). Dimers, trimers or tetramers of EoCen have nearly equal abilities of PKA phosphorylating Ser166. In turn, the phosphorylation reaction can change metal ion-induced self-assembly of EoCen. The self-assembly amount and velocity of phosphorylated EoCen were evidently reduced. The self-assembly mode can be reversed by the regulating factor KCl, but not by NaCl or LiCl. At high concentrations of KCl, the degree of EoCen self-assembly was higher than that of phosphorylated EoCen (EoCenp). There were no differences at low concentrations of KCl. Site III on EoCen may be responsible for controlling the balance between phosphorylation and self-assembly. Such results can provide valuable insights for understanding the molecular basis for centrin functions in resting or active cell mitosis.

Shunt capacitor bank on the 110kV side of ultra-high voltage (UHV) substation is mainly used for reactive power compensation and is an important part of UHV transmission system. Its normal and abnormal operation directly affects the safe operation of UHV substation. Therefore, it is of great practical significance to monitor the shunt capacitor bank on the 110kV side of UHV substation and obtain its running status in time. A real-time monitoring system of shunt capacitor bank on the 110kV side of UHV substation is developed based on the deep analysis of various operating conditions of shunt capacitor bank on the 110kV side of UHV substation. A monitoring system is developed to monitor the operation status of the shunt capacitors on the 110kV side of UHV substation in real time. The system provides the basis for further analyzing the operation status of the capacitor by measuring the current signal of single capacitor and detecting and analyzing the power frequency current and harmonic components in the current signal and recording current waveform.

Good atlases are defined for effective orbifolds, and a spark complex is constructed on each good atlas. It is proved that this process is 2-functorial with compatible systems playing as morphisms between good atlases, and that the spark character 2-functor factors through this 2-functor., Comment: 29 pages, final version

In particle digital holography,the process of determing focal distance is cumbersome and complex using traditional numerical reconstruction methods.Based on Hilbert-Huang transform,a method for detecting axial position of particle from in-line digital hologram is presented.The radial intensity distribution of single particle hologram is transformed by empirical mode decomposition which results in several intrinsic mode functions.The particle position can be determined by using liner regression of the first intrinsic mode function′s Hilbert spectrum.The validity and reliability are demonstrated by the theoretical simulation and experiments.Since it does not need to reconstruct the hologram,this method is expected to be used in real time digital particle hologram analysis.

A method on particles holograms analysis was proposed based on Hough transform and linear chirp transform.Particles sizes were calculated using the position of minimum point in space domain and frequency domain.After pretreatment of noise reduction filtering and edge detection to the holograms,string midpoint Hough transform was used to detect the center position of the particles,and the intensity distribution curve was described according to the cumulative normalized gray value of each circumference.Light intensity signal is applied to Fourier transform,combined with linear chirp transform for local spectral amplification,and then the accurate position of first minimum point in frequency domain can be known.Finally the particle sizes can be resolved by the obtained position in space and frequency domain.In terms of further particle spacing of particle holograms,numerical simulation results show that the method error were 2.5% or less.