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We present a model useful for interpretation of indentation experiments on animal cells. We use finite element modeling for a thorough representation of the complex structure of an animal cell. In our model, the crucial constituent is the cell cortex-a rigid layer of cytoplasmic proteins present on the inner side of the cell membrane. It plays a vital role in the mechanical interactions between cells. The cell cortex is modeled by a three-dimensional solid to reflect its bending stiffness. This approach allows us to interpret the results of the indentation measurements and extract the mechanical properties of the individual elements of the cell structure. During the simulations, we scan a broad range of parameters such as cortex thickness and Young's modulus, cytoplasm Young's modulus, and indenter radius, which define cell properties and experimental conditions. Finally, we propose a simple closed-form formula that approximates the simulated results with satisfactory accuracy. Our formula is as easy to use as Hertz's function to extract cell properties from the measurement, yet it considers the cell's inner structure, including cell cortex, cytoplasm, and nucleus.

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The endometrium lines the uterine cavity, enables implantation of the embryo, and provides an environment for its development and growth. Numerous methods, including microscopic and immunoenzymatic techniques, have been used to study the properties of the cells and tissue of the endometrium to understand changes during, e.g., the menstrual cycle or implantation. Taking into account the existing state of knowledge on the endometrium and the research carried out using other tissues, it can be concluded that the mechanical properties of the tissue and its cells are crucial for their proper functioning. This review intends to emphasize the potential of atomic force microscopy (AFM) in the research of endometrium properties. AFM enables imaging of tissues or single cells, roughness analysis, and determination of the mechanical properties (Young's modulus) of single cells or tissues, or their adhesion. AFM has been previously shown to be useful to derive force maps. Combining the information regarding cell mechanics with the alternations of cell morphology or gene/protein expression provides deeper insight into the uterine pathology. The determination of the elastic modulus of cells in pathological states, such as cancer, has been proved to be useful in diagnostics.

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Several copper(I) iminopyrrolidinates have been evaluated by thermogravimetric analysis (TGA) and solution based (1)H NMR studies to determine their thermal stability and decomposition mechanisms. Iminopyrrolidinates were used as a ligand for copper(I) to block previously identified decomposition routes of carbodiimide deinsertion and ß-hydrogen abstraction. The compounds copper(I) isopropyl-iminopyrrolidinate (1) and copper(I) tert-butyl-iminopyrrolidinate (2) were synthesized for this study, and compared to the previously reported copper(I) tert-butyl-imino-2,2-dimethylpyrrolidinate (3) and the copper(I) guanidinate [Me(2)NC((i)PrN)(2)Cu](2) (4). Compounds 1 and 2 were found to be volatile yet susceptible to decomposition during TGA. At 165 °C in C(6)D(6), they had half-lives of 181.7 h and 23.7 h, respectively. The main thermolysis product of 1 and 2 was their respective protonated iminopyrrolidine ligand. ß-Hydrogen abstraction was proposed for the mechanism of thermal decomposition. Since compound 3 showed no thermolysis at 165 °C, it was further studied by chemisorption on high surface area silica. It was found to eliminate an isobutene upon chemisoption at 275 °C. Annealing the sample at 350 °C showed further evidence of the decomposition of the surface species, likely eliminating ethene, and producing a surface bound methylene diamine.

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A copper(I) iminopyrrolidinate was synthesized and evaluated by thermal gravimetric analysis (TGA), solution based (1)H NMR studies and surface chemistry to determine its thermal stability and decomposition mechanism. Copper(I) tert-butyl-imino-2,2-dimethylpyrrolidinate (1) demonstrated superior thermal stability and showed negligible decomposition in TGA experiments up to 300 °C as well as no decomposition in solutions at 165 °C over 3 weeks.

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We report an accessible and simple method of producing 'black silicon' with aspect ratios as high as 8 using common laboratory equipment. Gold was sputtered to a thickness of 8 nm using a low-vacuum sputter coater. The structures were etched into silicon substrates using an aqueous H2O2/HF solution, and the gold was then removed using aqua regia. Ultrasonication was necessary to produce columnar structures, and an etch time of 24 min gave a velvety, non-reflective surface. The surface features after 24 min etching were uniformly microstructured over an area of square centimetres.

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A series of iminopyrrolidine (ip) compounds were synthesized with excellent yields as potential ligands for novel organometallic precursors for atomic layer deposition. The idea behind these ligands was that carbodiimide (CDI) deinsertion would not occur as the quaternary carbon was tethered to one chelate nitrogen. To our advantage a melting point trend was evident within the ip ligands and reflected in the family of heteroleptic aluminium species when the ip ligands were reacted with TMA or TEA. The alkane elimination reaction occurred at room temperature yielding clean products with high yields. Crystal structures were collected for compounds 7 [ipipAlMe(2)], 12 [tbipAlMe(2)], and 14 [sbipAlEt(2)] demonstrating that the heteroleptic aluminium species were dimers. This was also evident in the mass spectra collected for each compound as the parent peak was that of the dimer minus a methyl. Thermolysis studies were carried out on all the ipAlMe(2) species to observe the decomposition at an isotherm over several days. The decay of the methyl peak was monitored as a ratio against TMS within the solution and was shown to be a first order decomposition. From these studies it was clear that nbip (9), iso-bip (10), and tbip (12) were the most stable complexes with half-lives of 24.8, 9.00, and 10.3 days, respectively.