Papers by Keyword: Cells

Abstract: In-vitro cell culture offers the ability to grow individual cells and monitor their behaviour in a controlled environment over a certain time. During culture, different parameters have to be controlled to ensure a vital growth of cells. The most important parameters are temperature, pH-value, oxygen and carbon dioxide levels as well as the glucose concentration. All of these parameters influence the growth ability of the cell culture and should be monitored online. The online monitoring of glucose was achieved with a novel GOD based sensor which enabled a real-time measurement of glucose during cell culture. A first-time characterisation of the sensor was carried out in the culture medium DMEM. In addition, material properties of the culture system were investigated. At first to establish a baseline measurement, the sensor was placed in different glucose concentrations dissolved in Water-KCl mixture at 25 °C inside a batch chamber under constant stirring. Afterwards, the temperature was increased to 37 °C to simulate a cell culture environment. In addition, the system was transferred into a flow-through reaction chamber. The highest response signal and the most stable signal was achieved at 37 °C with DMEM during flow-through measurement. Based on these measurements online glucose monitoring in cell culture was possible to determine the glucose consumption for each cell which is important for future human-on-a-chip devices to prevent diabetic metabolisms.

Abstract: Biomimetic nanocrystalline apatites are analogous to bone mineral. They can be exploited not only for bone regeneration applications, but it is also possible to take advantage of their biomimetic features to explore novel domains of research such as in nanomedicine, if the nanoparticles are stabilized as a colloidal formulation. In this contribution, we concentrate on AEP/HMP-stabilized colloidal apatite nanoparticles (NPs) and on their interaction with different types of cells so as to get experimental evidence on their low cytotoxicity, non-proinflammatory potential, and good compatibility with Red Blood Cells. We then started to explore their interaction with an artificial free-standing phospholipid bilayer, as a simplified model for cell membranes: results indicate, for the first time, that these colloidal apatite NPs can modulate phospholipid bilayer membrane properties, and may even favor the permeation of small molecules (illustrated here with luminescent FITC), which could ultimately be exploited for nanomedicine applications in view of enhancing intracellular drug delivery.

Abstract: Abstract. The paper has built 3D-FEA models to simulate the electro-thermal behavior of Li-ion battery cells with Pouch Cell and Prismatic Cell by ANSYS. As for two models, the Li-ion battery system is simplified as a single equivalent battery layer (Pouch Cell) or multiple equivalent battery layers (Prismatic Cell) with the equivalent electrodes and separator. They were simulated under air cooling conditions. Simulations were compared with available battery temperature measurements. This shows that the 3D electro-thermal model applied in this study characterizes the electro-thermal behavior of the Li-ion battery cells reasonably well.

Abstract: This paper investigates the use of PCL and PCL/PLA scaffolds, produced using a novel additive biomanufacturing system called BioCell Printing, for bone tissue engineering applications. Results show that the BioCell Printing system produces scaffolds with regular and reproducible architecture, presenting no toxicity and enhancing cell attachment and proliferation. It was also possible to observe that the addition of PLA to PCL scaffolds strongly improves the biomechanical performance of the constructs.

Abstract: The microstructural evolution of a quenched medium-C steel during tempering was analyzed by means of Orientation Imaging Microscopy (OIM). The steel was heat treated in order to develop fully martensitic microstructures after quenching with a different prior austenite grain size (AGS). Main results can be summarized as below: A very poor effect of AGS on packet size was found in comparison to bainitic steels. A finer packet was measured at mid-thickness with respect to surface after the quenching process. This phenomenon was attributed to the effect of thermal strain path on phase transformation during quenching. The through-thickness microstructural gradient remains after tempering. High-angle boundary grains do not significantly grow after tempering; on the contrary, low-angle grain boundaries (cells) move, fully justifying the hardness evolution with tempering temperature.

Abstract: Unambiguous and thorough knowledge of interactions between cells and nanoparticles was necessary for applications of nanoparticle in living system. In this report we presented systematic studies of fabrication of inorganic nanoparticles and the application of entering into cells. Size distribution, zeta potential and transmission electron microscope (TEM) were performed to characterize the nanoparticles structure and define the mechanism by which nanoparticles are capable of entering into cells. The study revealed nanoparticles can entered cells via penetrating through the lipophilic bilayer, which should be paid attention to for inspirational value insome application researches and will be harmful in other cases.

Abstract: For the engine cells performance deterioration and fault diagnostics, the cells operation contributions to engine parameters changes are analyzed to account for the cells deterioration impact on parameters deviation to the EPR based baselines which are optimally modeled by polynomial regression method. The cells performance evaluation strategies for the engine type in this study are achieved through the WF-EGT, (N1-N2)-P25/P2, P3/P2-EGT linear correlation match and baseline deviation analysis and applied for verification.

Abstract: The acoustic properties of aluminum foams by gas injection method were studied experimentally. The micro and macro structure of aluminum foam with closed cells were observed by optical microscope (OM) and scanning electron microscope (SEM). The special structure of the closed-pores of the aluminum foams have leaded to good performance of the sound absorption based on three mechanisms: Helmholtz resonance, cell wall vibration and viscous and thermal effects. The effect of cell sizes, thickness of aluminum foams has been investigated and the cavity set at the back of the foam samples on the sound absorption efficiency of the foams has been measured. Analytical models of membrane vibrations were used to explain the sound absorption capacity of the foams.

Abstract: The microstructure evolution of Al-Cu alloys with different compositions is investigated in directional solidification. Two distinctly different microstructure evolution mechanisms are obtained in Al-0.85%Cu and Al-4%Cu systems, respectively. In Al-0.85%Cu alloy, it shows a peculiar phenomenon, the microstructure evolution is always cells and no dendrites are obtained. In other words, the cells undergo several transitions as the pulling velocity increasing from 15μm/s to 300μm/s, they follow the sequences: mixed microstructure of pox and banded cells →mixed microstructure of polygonal and banded cells →banded cells →elongated cells. Particularly, it is studied what caused the dendrites not appear in Al-0.85%Cu system. Finally, it comes to the conclusion that there are two aspects which lead to the phenomenon: a dilute alloy composition and a relatively higher temperature gradient.

Abstract: Photo-thermal imaging (PTI) is an imaging technique that can provide a resolution exceeding the diffraction limit. The theoretical resolution limit is less than 1 nm, therefore it is particularly suited to analyse particles in nano-size targets. It is also a non-labelling, high temporal resolution technique that can be conducted in a normal live cell environment. In this paper, a PT imaging microscopy system has been demonstrated and the integrity of the system is verified through a series of experiments on different samples, including red polystyrene bead and carbon nano-tube. The PTI technique can find further applications in biology studies for the visualization of cell organelles and apoptosis studies.