Optimization of large-scale fiber sensor arrays incorporatingmultiple optical amplifiers. Part II: pump power

For part I see, ibid., p. 218, 1998. We discuss how to minimize the pump power required for large-scale fiber sensor arrays employing erbium-doped fiber amplifier (EDFA) telemetry with respect to the number of amplifiers per bus, number of sensors per rung, and the gain per amplifier. For a large array, the pump power requirement is dominated by passive component losses along the array. We investigate several methods, including alternative array topologies, to reduce the power requirement while minimizing the impact on the signal-to-noise ratio (SNR). We define an optimum topology which requires less than 1 W of 1480 nm pump power per bus to support 200 high sensitivity (1 μrad/√(Hz)) sensors on a pair of fiber buses, a power requirement that is reasonable and attainable with available laser diodes     

Dysregulated expression of CD66a (BGP, C-CAM), an adhesion molecule of the CEA family, in endometrial cancer

CD66a (BGP, C-CAM) is an adhesion molecule of the carcinoembryonic antigen family that has been shown to be down-regulated in colorectal, prostate, and breast cancers. The purpose of the present study was to determine its expression pattern in the normal human endometrium and in endometrial neoplasia. For this purpose, we performed immunohistochemistry using the 4D1/C2 monoclonal antibody on a series of 24 normal endometrial samples and 47 endometrial carcinomas. Strong CD66a expression was observed in glandular and luminal epithelial cells of the normal endometrium with a consistent localization at the apical poles of these cells throughout the cycle. In late secretory (premenstrual) phase, loss of cellular polarity resulted in a membranous expression pattern in some glandular cells. In the analyzed tumor samples increasing areas with a complete loss of expression were observed with increasing malignancy grade. The apical expression pattern of the normal epithelium was changed to a membranous all-around pattern in 55% of the tumors, mostly in solid areas. This change correlated with malignancy grade and could be observed in 3 of 15 G1 tumors, 4 of 12 G2 tumors, 11 of 12 G3 tumors, and 8 of 8 serous-papillary carcinomas. Areas with membranous expression pattern could be observed along with areas with a normal apical expression pattern in lower grade carcinomas and with areas with complete loss of expression in high grade tumors. Northern blot analysis showed a loss of mRNA expression in tumor samples and HEC-1B endometrial adenocarcinoma cells. Loss of protein expression in the tumor samples was also observed by Western blot. In conclusion, CD66a protein expression is dysregulated in endometrial carcinomas, showing reduction or loss of expression with increasing malignancy grade and a change from the apical to a membranous localization.     

The influence of peripheral load on resetting voluntary movement by cortical stimulation: importance of the induced twitch

Hepatitis E has been the predominant type of acute hepatitis in Nepal both in adults and children, in sporadic and epidemic forms. We examined six hepatitis E virus (HEV) isolates obtained during an 8-year period, from 1987 to 1995, in the Kathmandu valley of Nepal. Analysis of portions of the putative helicase, polymerase and capsid genes demonstrated close genetic relatedness among themselves (> 96.4% identity) and with the Burmese (> 95.5%) and Indian (> 95.3%) isolates, and less so with the African (> 94.4%) and the Chinese (> 91%) isolates within the Asian genotype. Phylogenetic analysis placed the Nepali isolates in the Burma-India evolutionary branch and showed that the oldest isolate, TK78/87 was more similar to the Burmese isolates whereas the most recent isolates were closer to the Indian ones. Assuming no frameshifts, the Nepali isolates showed high amino acid conservation, but also unique changes when compared to other HEV isolates. Amino acid residue 614 of the capsid protein was identified as a possible marker to distinguish the Burma-Nepal-India from the China-Central Asian Republics subgenotype, and the Mexico genotype.     

Interferon-alpha therapy for hepatitis C virus recurrence after liver transplantation: long-term response with maintenance therapy

This paper considers the contributions by age of the various major groups of deaths to the increase in life expectancy at birth between 1980 and 1990 for both sexes in Singapore. Sixteen cause groups were used in the study. The data were analysed using LIFETIME, a personal computer package with a wide variety of methods for mortality investigations. Respiratory diseases made the largest contribution to the increase in life expectancy for both sexes. In contrast, ischaemic heart disease made a negative contribution of 1% in the gain in female life expectancy but contributed 12% improvement for males. Life tables for Singaporean males and females in the year 2000 were projected by extrapolating the mortality trends observed in earlier periods. The calculations show that the life expectancy at birth in the year 2000 to be 74.72 years for males and 79.48 years for females.     

Polarized Superfluorescent Fiber Sources

We report the theoretical and experimental performance of new, linearly polarized superfluorescent fiber sources (SFS). Internal polarization is produced either by splicing a fiber polarizer at an optimum location along a standard Er-doped SFS or by using a single-polarization Er-doped fiber. Numerical simulations predict that when operated in the backward, forward, or double-pass configuration, these SFSs produce nearly twice the power in the desired linear polarization as a standard, unpolarized SFS. This efficiency figure depends weakly on the polarizer location and extinction ratio, but requires a low polarizer insertion loss ( < 0.5 dB). Laboratory prototypes of a backward and a forward polarized SFS are presented that exhibit a power output in the desired linear polarization about 1.75 times larger than that of an unpolarized SFS, and an extinction ratio in excess of 17.5 dB.     

Acyclic diene metathesis polymerization: The synthesis of unsaturated polyketones

The first acyclic diene metathesis (ADMET) polymerization of unsaturated ketone containing monomers using the molybdenum catalyst, Mo(CHCMe₂Ph)(N-2,6-C₆H₃-i-Pr₂)[OCCH₃(CF₃)₂]₂ is reported. 6,6,8,8-Tetramethyl-1,12-tridecadiene-7-one undergoes homopolymerization; copoly-merizations are carried out with 1,9-decadiene and 2,12-dimethyl-2,12-dipentenylcyclododecan-1-one, 2,12-diallylcyclododecan-1-one, and trans-2,12-diallyl-2,12-dimethylcyclododecan-1-one These polymerizations are initiated under bulk conditions and are continued in solution. No evidence of Wittig chemistry is observed between the carbonyl functional group and the catalyst when a high degree of steric hindrance exists around the carbonyl moiety. Polymer structures were characterized by IR, ¹H NMR, and ¹³C NMR spectroscopy. Molecular weights were determined by endgroup analysis and gel permeation chromatography.     

Efficient, global-scale quantification of absolute protein amounts by integration of targeted mass spectrometry and two-dimensional gel-based proteomics

Knowledge on absolute protein concentrations is mandatory for the simulation of biological processes in the context of systems biology. A novel approach for the absolute quantification of proteins at a global scale has been developed and its applicability demonstrated using glucose starvation of the Gram-positive model bacterium Bacillus subtilis and the pathogen Staphylococcus aureus as proof-of-principle examples. Absolute intracellular protein concentrations were initially determined for a preselected set of anchor proteins by employing a targeted mass spectrometric method and isotopically labeled internal standard peptides. Known concentrations of these anchor proteins were then used to calibrate two-dimensional (2-D) gels allowing the calculation of absolute abundance of all detectable proteins on the 2-D gels. Using this approach, concentrations of the majority of metabolic enzymes were determined, and thus a quantification of the players of metabolism was achieved. This new strategy is fast, cost-effective, applicable to any cell type, and thus of value for a broad community of laboratories with experience in 2-D gel-based proteomics and interest in quantitative approaches. Particularly, this approach could also be utilized to quantify existing data sets with the aid of a few standard anchor proteins.     

Fabrication of low surface free energy automotive clear coats: Mechanical and surface chemistry studies

This work aims at improving the surface chemistry and the mechanical properties of a commercial acrylic–melamine clear coat using a functional siliconized additive. The resistance of films against biological degradation was then investigated using pancreatin (simulated bird droppings) and Arabic gum (simulated tree gum). Variations in the surface and bulk chemical structures, as well as the thermomechanical characteristics of the clear coats at different concentrations of the additive, were investigated by a wide range of techniques inclusive of contact angle measurement, gonio‐spectrophotometery, dynamic mechanical thermal analysis (DMTA), energy‐dispersive spectroscopy, atomic force microscope, optical microscope, and attenuated totalreflectance Fourier transform infrared (ATR‐FTIR) spectroscopy. Negligible effect of additive on color change was revealed. It was shown that even at low loadings of additive it could migrate to the surface, producing hydrophobic films with very low surface free energies with water contact angle exceeding 100°. In addition, it was found by DMTA and ATR‐FTIR studies that the functional additive was covalently attached to the acrylic–melamine chains through its hydroxyl groups. However, phase separation was observed at high concentrations of additive, leading to reduced crosslinking density. The clear coat resistance against pancreatin and Arabic gum was improved using optimum concentrations of the additive. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013