Functional surgery of ceruminoma of the external and/or middle ear

We made a prospective study of 58 patients with suspected internal derangement of the knee. They were examined by magnetic resonance imaging using 3-D gradient echo intermediate-weighted studies before having an arthroscopy. The preoperative clinical assessment was found to have a diagnostic sensitivity of 77% and a specificity of 43%, compared with 100% and 63% respectively for magnetic resonance imaging. Comparison of magnetic resonance imaging and arthroscopy confirmed the accuracy of magnetic resonance imaging in the diagnosis of internal derangement but the results for articular cartilage lesions were much less good, with a sensitivity of only 18% but a specificity of 100%. Acceptance of the magnetic resonance imaging findings could have resulted in a 29% reduction in the number of arthroscopies without missing any significant meniscal lesion.     

Frequency of homozygous deletion at p16/CDKN2 in primary human tumours

BACKGROUND: Carcinoma of the breast is characterized by a variable course with prognosis dependent on disease stage at presentation. Paradoxically, some patients with early malignancy demonstrate disease progression within a short time. The role of tumor markers in the management of carcinoma of the breast is controversial. While CA15-3 is the most widely used tumor marker in carcinoma of the breast, its role in the management of patients with early disease is controversial. STUDY DESIGN: Since 1986, all patients presenting to our unit with carcinoma of the breast have had serial CA15-3 levels measured. This study evaluates the role of serial CA15-3 levels in the management of a consecutive series of 168 patients with Stage I disease at presentation. RESULTS: The mean preoperative CA15-3 levels at presentation were significantly elevated in patients with Stage I disease compared with patients with benign disease. Sixteen patients had either locoregional (five patients) or metastatic recurrence (11 patients). CA15-3 levels were not elevated in patients with locoregional disease and were significantly elevated in patients with bony metastases and gave a mean lead time of 6.3 months over bone scintigraphy. CONCLUSIONS: Serial CA15-3 measurements are an efficient and cost-effective method of monitoring disease progression and have advantages over conventional investigations in patients with early carcinoma of the breast.     

Bandgap Tuning of Silicon Micromachined 1-D Photonic Crystals by Thermal Oxidation

Fabrication and optical testing of high-aspect-ratio 1D photonic crystals, obtained by electrochemical micromachining of silicon, are discussed in this paper. The devices consist of high-aspect-ratio periodic (P=4 mum) arrays of 1.22-mum-thick silicon walls separated by 2.78-mum-wide air gaps, with 100 mum etching depth. They were designed as hybrid quarter-wavelength reflectors with photonic bandgaps in the near-IR region, one in particular centered at lambda=1.55 mum. The fabrication process was improved to increase structure uniformity and strength. Thermal oxidation of the silicon structures was exploited to tune the wavelength position and width of the bandgaps. Fabricated devices, also with different silicon dioxide thicknesses, were optically tested by measuring their spectral reflectivity in the wavelength range of 1.0-1.7 mum. Experimental results were found in good agreement with the calculated spectra.     

Modulus of elasticity of I-214 young poplar wood from standing trees to sawn timber: influence of the age and stand density

The poplar wood industry chain from planted forests takes a strategic position for the creation of a competitive, profitable, and highly technological bioeconomy in the world. Niche sectors such as buildings can find in poplar wood an effective ally to reduce its carbon footprint and ecological backpack. For the poplar wood, it is important to understand the huge significance of the proper silvicultural management of a plantation and to characterize the raw material. In this context, this paper carries out such characterization for the particular case of young plantations of the clone I-214 (Populus × euroamericana (Dode) Guinier), commonly used for its high growth rate. The acoustic non-destructive characterization of poplar wood is carried out from standing trees, logs and sawn timber and then compared with the one obtained through destructive mechanical tests. The study shows that growth parameters are highly affected by the age and moderately affected by stand density, while mechanical properties are strongly affected by the age and less affected by the stand density. The study also shows high values of the linear regression coefficients between the mechanical properties obtained on standing trees, logs, and sawn timber using non-destructive and destructive methods (R²?=?0.7 for all three cases), greater than those obtained for other species. A good linear fitting was obtained between the tree and log velocities (R²?=?0.76) and between the tree and log elastic moduli (R²?=?0.85). Consequently, the evaluation of the mechanical properties employing the optimized acoustic protocol provides a reliable characterization for the poplar wood.

     

Proton exchange membrane water electrolysis with short-side-chain Aquivion membrane and IrO2 anode catalyst

A series of three membrane types has been screened for medium temperature solid polymer electrolyte water electrolysis in membrane electrode assemblies coated with 2 mg cm⁻² of iridium oxide as a catalyst for the oxygen evolution reaction, synthesised via a hydrolysis method from the hexachloroiridic acid precursor, and deposited on the membrane either directly by spray deposition or by decal transfer. The short-side-chain perfluorosulfonic acid Aquivion^® ionomer of equivalent weight 870 meq g⁻¹, in membranes of thickness 120 μm, gives higher water electrolysis performance at 120 °C than a composite membrane of Aquivion^® with zirconium phosphate, while a sulfonated ether-linked polybenzimidazole, sulfonated poly-[(1-(4,4′-diphenylether)-5-oxybenzimidazole)-benzimidazole], shows promising performance and no transport limitations up to 2 A cm⁻². The lowest cell voltage was observed at 120 °C for an MEA prepared using spray-coating directly on the Aquivion^® membrane, 1.57 V at 1 A cm⁻².     

Testing of "Venetian-Blind" silicon microstructures with optical methods

In this paper, we illustrate the design and testing of new silicon microstructures, fabricated by means of a conventional planar process. These "Venetian-blind" structures consist of arrays of narrow, rectangular suspended masses (width =31 /spl mu/m, length =400 /spl mu/m, thickness =15 /spl mu/m), which can be tilted using electrostatic actuation. Characterization of their static and dynamic behavior was performed with optical methods. The diffraction patterns in monochromatic light were analyzed and vibration measurements were performed by means of semiconductor laser feedback interferometry: experimental data on the tilt angle as a function of the applied voltage and on the resonance frequencies are reported. A maximum tilt angle of approximately 1.9/spl deg/ was obtained with a driving voltage in the range of 70-95 V. All the tested devices showed resonance frequencies higher than 80 kHz, which is fast enough (i.e., switching time in the millisecond range) for future use in optical interconnections. Numerical analyses were performed to evaluate the coupled electromechanical behavior of the microstructures, confirming the observed experimental behavior.     

Effect of the antiarrhythmic drug procainamide on the toxicity and antitumor activity of cis-diamminedichloroplatinum(II)

The class I antiarrhythmic drug procainamide (Pd) was tested on BDF1 mice for its chemoprotective activity against cis-diamminedichloroplatinum(II) (DDP) toxicity. Pd at the dose of 50 mg/kg protected mice against otherwise lethal doses of DDP (survivors at Day 14 after 25 mg/kg DDP or 25 mg/kg DDP-Pd treatment: 0% vs 100%) and greatly reduced the weight loss induced by DDP. Moreover, the increased plasma urea nitrogen levels caused by a single ip administration of DDP in water (8 or 16 mg/kg) as well as the tubular degenerative changes detected by light microscopy were prevented by Pd. Pd had no effect on the sensitivity of P388 leukemic cells to DDP in vitro, but the administration of DDP (16 mg/kg) and Pd (50 mg/kg) to BDF1 mice bearing P388 leukemic cells produced a significant increase in survivals compared to mice receiving ip DDP alone diluted in 0.9% NaCl solution. The increased efficacy of this combination therapy in P388 leukemic mice compared to a single DDP treatment at the same dose was observed both when the drugs were administered ip simultaneously (p = 0.042) and when DDP and Pd were given ip and iv, respectively (p = 0.018). Since procaine, which differs from Pd merely in the replacement of the amide by the ester linkage, has also been reported to significantly enhance DDP efficacy (M. Esposito et al., 1990, J. Natl. Cancer Inst. 82, 677-684.), a comparison of their effects in tumored mice exposed to DDP has been made. Although both drug combinations were superior to that of DDP alone, in terms of both survival time and numbers of cures, Pd treatment seems to offer better protection against DDP-induced lethality than did procaine.     

Characterization of an ecto-phosphorylated protein of cultured cerebellar granule neurons

Previous work identified the phosphorylation by extracellular ATP of an endogenous 45-kDa protein substrate and established the presence of ecto-protein kinase activity associated with cultured cerebellar granule neurons (Volonté et al.: J Neurochem 63:2028-2037, 1994). In this work, we characterize such ecto-phosphorylated 45-kDa protein substrate and its association with the cellular membrane. The total radioactive content of the 45-kDa protein is stable for the first 15 min after phosphorylation, and decreases about 70% in 30 min and 90% in approximately 2 hr. Rinsing the cells after the phosphorylating reaction causes a 50% removal of the incorporated radioactivity. Glycosidic residues are present on the 45-kDa ecto-protein, which is held in position on the cellular membrane through a specific glycosyl-phosphatidylinositol anchor. The extracellular incorporation of phosphate on the 45-kDa protein is not modulated by agents interfering with cytoskeleton stability, such as colchicine and taxol, or by gangliosides. The extracellular phosphorylation occurs mostly on serine residues, since the phosphate ester linkage is unstable at high pH and only antibodies raised against phosphoserine are capable of recognizing the 45-kDa ecto-protein.     

Formaldehyde Oligomerization on Silicalite: An FTIR and NMR Study

Upon adsorption of formaldehyde onto silicalite, hydrogen-bonded adducts are formed between the (slightly acidic) SiOH groups of the purely siliceous zeolite and formaldehyde, as seen by using both FTIR and ¹H-NMR spectroscopies. These species then evolve to form polymerization products of the type –(CH₂O) _n –. On the contrary, when silicalite is contacted with trioxane hydrogen-bonded adducts are formed, but no polymerization ensues.     

Reengineering user interfaces

Most developers would like to avoid redesigning a system around a new interface. But turning a character-based interface into a graphical one requires significant time and resources. The authors describe how this process can be partially automated, giving the results of their own reverse-engineering effort