Development of Gel Droplet Microfluidic System for High Throughput Microbial Screening

Over the last few decades, droplet based microfluidics has received great attention and it is growing rapidly with interdisciplinary fields, such as biomedical, physics, chemical engineering, tissue engineering and even therapeutic area. Droplet based microfluidics offers uncountable potential in its applications ranging from a developing analytical system to precise controlling of the content inside the droplet. One of the most highlighted advantages of droplet based microfluidics is the capability of cell screening in high throughput manner, which results in significant reductions in cost and discovering new medicine or curing technology Nowadays, culturing encapsulated cell in 3D environment has been required and performed. Although conventional 2D culturing has simplicity of platform but because 3D environment has the capability of providing high throughput biological assays and an environment similar to native biological complexes, it was chosen for this study. Furthermore, the field of biomedical or biomaterials prefer to improve that 3D environment to be much closer to genuine systems. From this respect, hydrogels have been proven and replaced as a useful platform for 3D cell culture applications in microfluidics and cell laden hydrogel droplet is one of the most popular application with their flexibility similar to natural tissue and mild gelation method. In this thesis, we studied two different types of hydrogel droplets and developed a strategy for the microbial co-culture platform from the ‘platform’ perspective. This thesis focuses on the microfabrication to pattern silicon wafer ii mold for the mass production and creating polydimethylsiloxane (PDMS) devices. With this transparent hydrophobic material, hydrogel droplet generation, on-chip cross linking and manipulation could be possible

High temperature X-ray diffraction and Landau theory investigation of order-disorder transition in defect NaCl-type solids

The nature of the order-disorder transitions in a series of NaCl-type materials was investigated using high-temperature powder x-ray diffraction. The Landau theory of symmetry and phase transitions was applied to interpret the continuous thermal symmetry-breaking transitions, and all possible thermal symmetry-breaking transitions starting from the rock-salt type structure were determined. Known examples together with those which have been observed in this work are reported. The diffraction data were analyzed by modified Rietveld-type full profile refinement;In defect NaCl-type materials, Zr[subscript] 1-xS, NbN[subscript] 1-x and Y[subscript] 1-xSe, the order-disorder transitions occur with a variety of ordered superstructures: (a) In the zirconium-sulfur case, Zr[subscript]0.75S, the order-disorder transition occurred at about 1250° to form a superstructure with R3m symmetry by vacancy ordering in alternate planes perpendicular to a body diagonal of the cubic Fm3m cell. (b) In the nitrogen deficient niobium nitride system, the NaCl-type structure of NbN[subscript]0.77 at high temperature transforms continuously to form a tetragonal phase at low temperature by the combination of vacancy ordering and displacive motion. The space group I4/mmm was found. (c) The vacancies in defect yttrium monoselenide order at about 275°, and this ordering transition corresponding to the L point of the Brillouin zone yielded a cubic 2 x 2 x 2 superstructure. Two space groups were found to be possible for this superstructure: Fm3m and Fd3m. Refined values for individual isotropic thermal parameters indicate that the structure with Fd3m symmetry is the correct one;Some other nonstoichiometric compounds with vacancy ordering were investigated: (a) In the Y-Se system a new phase, Y[subscript] 5- xSe[subscript]7, was found and the crystal structure was determined by single-crystal and powder x-ray diffraction studies. (b) A new intermediate phase in the Lu-S system, Lu[subscript] 2+xS[subscript]3, between the sulfur-rich end of the monosulfide homogeneity range and Lu[subscript]2S[subscript]3, was found to be isostructural with Sc[subscript]2S[subscript]3. (c) The previously reported structure of nitrogen deficient (N/Cr = 0.46) Cr[subscript]2N was confirmed and refined based on single-crystal data. (d) A series of samples in the composition range TiO[subscript]1.0~ TiO[subscript]1.5 was examined by high-temperature x-ray diffraction

Unintended complication of intracranial subdural hematoma after percutaneous epidural neuroplasty.

Percutaneous epidural neuroplasty (PEN) is a known interventional technique for the management of spinal pain. As with any procedures, PEN is associated with complications ranging from mild to more serious ones. We present a case of intracranial subdural hematoma after PEN requiring surgical evacuation. We review the relevant literature and discuss possible complications of PEN and patholophysiology of intracranial subdural hematoma after PEN