Polymer coating behavior of Rayleigh-SAW resonators with gold electrode structure for gas sensor applications

Results from systematic polymer coating experiments on surface acoustic wave (SAW) resonators and coupled resonator filters (CRF) on ST-cut quartz with a corrosion-proof electrode structure entirely made of gold (Au) are presented and compared with data from similar SAW devices using aluminium (Al) electrodes. The recently developed Au devices are intended to replace their earlier Al counterparts in sensor systems operating in highly reactive chemical gas environments. Solid parylene C and soft poly[chlorotrifluoroethylene-co-vinylidene fluoride] (PCFV) polymer films are deposited under identical conditions onto the surface of Al and Au devices. The electrical performance of the Parylene C coated devices is monitored online during film deposition. The PCVF coated devices are evaluated after film deposition. The experimental data show that the Au devices can stand up to 40% thicker solid films for the same amount of loss increase than the Al devices and retain better resonance and phase characteristics. The frequency sensitivities of Au and Al devices to parylene C deposition are nearly identical. After coating with soft PCFV sensing film, the Au devices provide up to two times higher gas sensitivity when probed with cooling agent, octane, or tetrachloroethylene.     

Comparison of initial fixation strength between biodegradable and metallic interference screws and a press-fit fixation technique in a porcine model

We describe nuchal cord changes in four children with os odontoideum who had cervical spine magnetic resonance imaging (MRI) before surgery. In these four children, nuchal cord changes consistent with previous trauma were seen. The presence of the nuchal cord changes supports the concept of trauma as an etiologic factor in these four cases. This study supports trauma as an associated factor in patients with os odontoideum.     

Effects of autografting ovarian tissue,ovariectomy and implanting on growth rate and carcass characteristics of feedlot heifers

Ninety heifers sired by Charolais or Red Poll bulls were utilised in two trials involving ovariectomy, ovarian tissue transplants (autografts) andlor an anabolic implant. In trial 1, four treatments were imposed upon 60 heifers: (1) autograft, (2) autograft plus Synovex-H® implant, (3) vaginal ovariectomy plus implant, and (4) intact plus implant. Three replications of five heifers per treatment were fed a finishing diet until heifers weighed approximately 432 kg. Autografed-implanted heifers exhibited a greater average daily gain than non-implanted autografted heifers (P < 0.05). No treatment effects were detected for feed eficiency or dressing percentage. Carcasses from autografted heifers merited higher marbling scores and USDA quality grades than did those of ovariectomised-implanted heifers. Fat thickness tended to be greater for autografted heifers than for heifers in the implant treatment groups (P <0.l0). Non-implanted autografted heifers had smaller ribeye areas, more kidney, pelvic and heart fat, and higher numerical USDA yield grades. Shear force values and taste panel scores for meat favoured non-implanted autografted heifers. In trial 2, 30 heifers were autografted, ovariectomised via high lumbar laparotomy, or left as intact controls. Heifers in trial 2 were fed a finishing diet until heifers reached 1.2 ern average backfat thickness. Intact heifers tended to gain weight more rapidly than did ovariectomised heifers. Ovarian cell types were detected at the graft sites of only four of the 10 autografted heifers upon post-mortem histological examination. Very low levels of oestrogen were present in the fluid aspirated from three of the apparently successful grafts. However, growth rate was not superior for these three heifers.     

Bursting in the LMS algorithm

The least mean square (LMS) algorithm is known to converge in the mean and in the mean square. However, during short time periods, the error sequence can blow up and cause severe disturbances, especially for non-Gaussian processes. The paper discusses potential short time unstable behavior of the LMS algorithm for spherically invariant random processes (SIRP) like Gaussian, Laplacian, and K₀. The result of this investigation is that the probability for bursting decreases with the step size. However, since a smaller step size also causes a slower convergence rate, one has to choose a tradeoff between convergence speed and the frequence of bursting     

High level expression of the IL-1 receptor related T1 receptor in insect cells

Baculovirus-dependent expression of membrane-associated and secreted, heavily modified proteins in insect cells often results in low yields. To optimize expression of T1, a heavily glycosylated receptor related to Interleukin-1 receptor type I, deletion mutants comprising either the heavily glycosylated extracellular domain or the isolated transmembrane and cytoplasmic portions of the T1 receptor were expressed from recombinant baculoviruses. As shown here, the use of a Baculovirus-derived leader sequence (GP67) in combination with an insect cell line with increased secretory capacity resulted in yields of several mg per liter (10(9) cells) of culture of both purified secretory T1 glycoprotein and membrane-associated T1 receptor.     

Calculation of phase equilibria in systems containing water and supercritical components

The Redlich-Kwong equation of state was used in both the liquid and vapour phases to calculate vapour-liquid equilibria in binary and ternary systems c