The evolution of silica nanostructure morphology induced by local Si vapor source concentration gradient has been investigated by a smart design of experiments. Silica nanostructure or their assemblies with different morphologies are obtained on photoresist-derived three-dimensional carbon microelectrode array. At a temperature of 1,000°C, rope-, feather-, and octopus-like nanowire assemblies c...

The motile responses of Dictyostelium discoideum amoebae to a cyclic AMP (cAMP) concentration gradient were examined using a novel assay system. In this system, a cAMP concentration gradient was generated, while the overall cAMP concentration could be either increased or decreased in a chamber containing amoebae. The chemotactic responses of amoebae were examined immediately after they had been...

Many biological processes are regulated by gradients of bioactive chemicals. Thus, the generation of materials with embedded chemical gradients may be beneficial for understanding biological phenomena and generating tissue-mimetic constructs. Here we describe a simple and versatile method to rapidly generate materials containing centimeter-long gradients of chemical properties in a microfluidic...

objective: the aim of this study was to examine the efficiency of ha-binding test and sperm gradient processing method for the selection of sperm with normal protamine, intact dna and normal morphology. materials and methods: the study was conducted on 29 patients undergoing icsi. semen analysis was carried out according to who criteria. semen samples were divided into three equal portions. one...

A microfluidic diffusion diluter was used to create a stable concentration gradient for dose response studies. The microfluidic diffusion diluter used in this study consisted of 128 culture chambers on each side of the main fluidic channel. A calibration method was used to find unknown concentrations with 12% error. Flow rate dependent studies showed that changing the flow rates generated diffe...

A new learning strategy is proposed for training of radial basis functions (RBF) network. We apply two different local optimization methods to update the output weights in training process, the gradient method and a combination of the gradient and Newton methods. Numerical results obtained in solving nonlinear integral equations show the excellent performance of the combined gradient method in ...

Background: During ICSI, motile sperm with normal morphology are selected and injected into oocyte. But integrity of chromatin is not observable. Therefore, researchers are trying for to present novel method of sperm selection with high percentage of normal chromatin. HOST test is a useful assay of functional integrity of the human sperm membrane. We decide to use HOST test after DGC for infert...

The disc diffusion method, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and gradient-plate techniques were implemented to evaluate the antibacterial activity of honey and propolis against Staphylococcus aureus and Escherichia coli. The growth of S. aureus was inhibited by application of propolis and honey at concentrations of 2.74 to 5.48 mg ml and 375.0 at m...