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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.

Esophageal cancer, including esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC), shows high incidence and poor prognosis. The early detection and endoscopic treatment of (pre)malignant lesions of esophageal cancer significantly improve disease outcomes of patients. However, the high-definition white-light endoscopy followed by random biopsy is reported with a non-ignorable miss rate. The development of advanced endoscopic techniques, such as fluorescence molecular endoscopy (FME) and endocytoscopy, can aid endoscopists in diagnosing early (pre)malignant lesions in vivo. FME realizes wide-field molecular imaging under endoscopy, which serves as a red flag technique for endoscopists by fluorescently highlighting the disease-specific molecule. In Chapter 3 and 4, we identified suitable target proteins and developed near-infrared fluorescent tracers for FME to detect ESCC and EAC at an early stage. In Chapter 6, we investigated the feasibility of assessing pathological response of EAC patients after neoadjuvant chemoradiotherapy by Bevacizumab-800CW guided FME. Endocytoscopy is a pin-point imaging technique that provides endoscopists with magnified optical cellular morphology and subcellular characteristics, referred to as an optical biopsy. In Chapter 5, we developed a classification criteria, an online training module for clinicians and a computer-aided diagnosis (CAD) algorithm based on in vivo images of fourth-generation endocytoscopy to distinguish dysplastic from non-dysplastic Barrett's esophagus tissue. We further investigated the interaction of this CAD algorithm with the clinicians.

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.

Non-orthogonal multiple access(NOMA) can improve spectrum efficiency and support massive connectivity by the use of resources in non-orthogonal way, which is expected to become one of the key technologies of 5G. Considering the situation that the base station(BS) is equipped with multiple antennas，this paper proposes a compressive sensing(CS) based sparsity adaptive matching pursuit hard fusion algorithm(SAMP-HFA) to realize multi-user detection(MUD) for uplink grant-free single-input multiple-output non-orthogonal multiple access(SIMO-NOMA) systems where the number of active user is unknown. The proposed algorithm consists of three steps. Firstly, it detects the user activity information by conventional SAMP algorithm at each antenna, and then amalgamates the detected user activity information to obtain a common active user set. Finally, the users′ data can be detected by the obtained active user set. The results show that the proposed SAMP-HFA demonstrates significant performance gain in terms of bit error rate(BER) with the number of antennas increases.

Carbonic anhydrase (CA) inhibitors have a long history of safe clinical use as mild diuretics, in the treatment of glaucoma and for altitude sickness prevention. In this study, we aimed to determine if CA inhibition may be an alternative approach to control thrombosis. We utilized a high-resolution dynamic imaging approach to provide mechanistic evidence that CA inhibitors may be potent anti-procoagulant agents in vitro and effective anti-thrombotics in vivo. Acetazolamide and methazolamide, while sparing platelet secretion, attenuated intracellular chloride ion entry and suppressed the procoagulant response of activated platelets in vitro and thrombosis in vivo. The chemically similar N-methyl acetazolamide, which lacks CA inhibitory activity, did not affect platelet procoagulant response in vitro. Outputs from rotational thromboelastometry did not reflect changes in procoagulant activity and reveal the need for a suitable clinical test for procoagulant activity. Drugs specifically targeting procoagulant remodeling of activated platelets, by blockade of carbonic anhydrases, may provide a new way to control platelet-driven thrombosis without blocking essential platelet secretion responses.

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.

Powder mixing is an essential operation in various industrial fields, such as pharmaceuticals, agro-food, cements, etc. Continuous powder mixing, as an alternative to conventional batch mixing, has attracted a lot of interest mainly due to its capacity in handling high volume manufacturing. This work aims at the contribution to the implementation of process control applications for powder mixing in a pilot-scale continuous mixer. Prior to developing process control strategies, new developments have been presented for better understanding continuous mixing of two components. Hold-up weight and relative hold-up weight distribution of each component in the whole mixer have been experimentally investigated under different operating conditions. An improved Markov chain model has been finally presented to predict the mean concentration of the mixtures obtained at the mixer's outlet. The implementation of a proportional-integral-derivative (PID) controller has been experimentally performed as an initial attempt to real-time control the homogeneity of the mixture produced. The rotational speed of the stirrer, identified as an important deciding factor towards the mixer's efficiency, has been considered as the manipulated variable. The closed-loop control is based on either the mean concentration or the relative standard deviation. The performances of the proposed closed-loops have been evaluated for continuous mixing subjected to step changes in feed rates of the mixer. Four case studies have been defined and presented. The main challenge in the process control system is the tuning of PID parameters. The performance of closed-loop control of either the mean concentration or the relative standard deviation has been compared to open-loop operation.; Le mélange de poudres est une opération essentielle dans divers domaines industriels, tels que les produits pharmaceutiques, agro-alimentaires, ciments, etc. Le mélange de poudres en continu, comme alternative intéressante au mélange conventionnel en batch, suscite beaucoup d'intérêt surtout en raison de sa capacité à gérer de grands volumes de production. Ce travail vise à contribuer à l'implémentation des applications de contrôle-commande. Avant de développer des stratégies de contrôle-commande, de nouveaux développements ont été présentés pour mieux comprendre le mélange continu de deux composants. La masse retenue et la répartition relative de la masse retenue de chaque composant dans le mélangeur ont été étudiées et prédites sous les différentes conditions opératoires. L'amélioration d'un modèle basé sur les chaînes de Markov a été finalement présentée pour prédire la concentration moyenne des mélanges obtenus à la sortie du mélangeur. L'implémentation d'un contrôleur PID a été expérimentalement réalisée comme une première tentative pour contrôler en temps réel l'homogénéité du mélange produit. La vitesse de rotation du mobile d'agitation, identifiée comme un facteur important influençant l'efficacité du mixer, a été considérée comme la variable manipulée. La commande en boucle fermée est basée, soit sur la concentration moyenne, soit sur le coefficient de variation. Les performances des boucles fermées proposées ont été évaluées pour le mélange continu subi à des changements d'échelon dans les débits d'alimentation du mélangeur. Quatre études de cas ont été définies et présentées. Le défi principal dans le système de contrôle-commande est le réglage des paramètres PID. La performance de commande en boucle fermée soit de la concentration moyenne, soit du coefficient de variation a été comparée à l'opération en boucle ouverte.