Efficient diode-pumped single-frequency erbium:ytterbium fiberlaser

We report a 7.6-mW single-frequency fiber laser operating at 1545 nm, using for the first time an Er³⁺:Yb³⁺ doped fiber and a fiber grating output coupler. The laser did not exhibit self-pulsation, which is a typical problem in short three-level fiber lasers, and had a relative intensity noise (RIN) level below -145.5 dB/Hz at frequencies above 10 MHz. The linewidth of the laser was limited by the relaxation oscillation sidebands in the optical spectrum and was typically less than 1 MHz     

Outplacement: Client characteristics and outcomes.

Outplacement firms developed in response to corporate downsizings to assist former upper-level employees in seeking reemployment. An important question for practitioners who assist clients in outplacement is how the personal characteristics that clients bring to the situation influence their success in finding a new job. The present archival study examined demographic variables, previous job history, and personality characteristics as predictors of outplacement outcomes. Outplacement duration was predicted by previous income, and new earnings were predicted by previous earnings, sex, and years with previous employer. The need for prospective, longitudinal research that examines the coping process in outplacement is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conception assistée par ordinateur des circuits intégrés monolithiques hyperfréquences

Computer aided design of microwave monolithic integrated circuits must combine two different fields. The first domain is the simulation of microwave circuits taking into account non linear aspects development of time domain and harmonic balance simulation algorithms specialized for microwave circuits. In the second place are found, the layout algorithms which were developed for logic circuits (on Si or GaAs). The association of these two types of algorithms leads to the constitution of aCad workstation for microwave monolithic integrated circuits. Two examples of design and realization of integrated circuits with these tools are presented.     

Smashing peacocks further: drawing quasi-trees from biconnected components

We extend the popular force-directed approach to network (or graph) layout to allow separation constraints, which enforce a minimum horizontal or vertical separation between selected pairs of nodes. This simple class of linear constraints is expressive enough to satisfy a wide variety of application-specific layout requirements, including: layout of directed graphs to better show flow; layout with non-overlapping node labels; and layout of graphs with grouped nodes (called clusters). In the stress majorization force-directed layout process, separation constraints can be treated as a quadratic programming problem. We give an incremental algorithm based on gradient projection for efficiently solving this problem. The algorithm is considerably faster than using generic constraint optimization techniques and is comparable in speed to unconstrained stress majorization. We demonstrate the utility of our technique with sample data from a number of practical applications including gene-activation networks, terrorist networks and visualization of high-dimensional data     

Fully Automatic Visualisation of Overlapping Sets

Visualisation of taxonomies and sets has recently become an active area of research. Many application fields now require more than a strict classification of elements into a hierarchy tree. Euler diagrams, one of the most natural ways of depicting intersecting sets, may provide a solution to these problems.
In this paper, we present an approach for the automatic generation of Euler-like diagrams. This algorithm differs from previous approaches in that it has no undrawable instances of input, allowing it to be used in systems where the output is always required. We also improve the readability of Euler diagrams through the use of Bézier curves and transparent coloured textures. Our approach has been implemented using the Tulip platform. Both the source and executable program used to generate the results are freely available.     

Characterization of the binding site for inhibitors of the HPV11 E1-E2 protein interaction on the E2 transactivation domain by photoaffinity labeling and mass spectrometry

An indandione-containing class of inhibitors abrogates DNA replication of human papillomavirus (HPV) types 6 and 11 by binding reversibly to the transactivation domain (TAD) of the viral E2 protein and inhibiting its interaction with the viral E1 helicase. To locate the binding site of this class of protein-protein interaction inhibitors, a benzophenone derivative was used to generate an irreversibly labeled E2-TAD polypeptide. The single site of covalent modification of the E2-TAD was identified by proteolytic digestions using trypsin, LysC, and V8 proteases and characterization of the resulting peptides by LC-MS procedures. Through this methodology, the benzophenone attachment point was located at the terminal methyl of residue Met101. Evidence further pinpointed the site of photoaffinity attachment to the terminal carbon atom, which is significant in providing a definitive example of the ability to locate photoinduced cross-linking to a polypeptide with atomic resolution using solely mass spectrometric detection. The location of the inhibitor binding site vis-à-vis the Glu39 and Glu100 residues sensitive to mutation for HPV 11 E2-TAD is discussed in relation to the crystal structure of the E2-TAD from the related HPV type 16.     

Inverse resolution of the heat-transfer equation with internal heat source: Application to the quenching of steels with phase transformations

A method is described for calculating the time dependence of the temperature and heat flux (on heating and cooling) at the surface of a solid body. For a given ambient temperature and a known time-temperature function of an interior point, the surface heat flux is computed through an inverse conduction algorithm taking into account the nonlinear nature of the problem. Moreover, this algorithm includes the enthalpy of phase transformations. The influence of space and time steps on inverse calculations (precision, stability) is investigated. The method is then applied to thermal cases involving different transformations in steels.     

Comparative effects of felodipine ER, amlodipine and nifedipine GITS on 24 h blood pressure control and trough to peak ratios in mild to moderate ambulatory hypertension: a forced titration study

OBJECTIVE: To evaluate the 24 h antihypertensive efficacy and duration of action of felodipine extended release (ER) in comparison with two other long acting dihydropyridine calcium antagonists, amlodipine and nifedipine gastrointestinal therapeutic system (GITS), in patients with mild to moderate essential hypertension substantiated by ambulatory blood pressure (BP) monitoring. DESIGN: Randomized, forced titration, parallel group study. Clinic BP was measured at every patient's visit, and 24 h ambulatory BP was monitored at baseline and at the end of each dose-titration period. SETTING: Single centre: hypertension research unit in Quebec City, Quebec. PATIENTS: There were 89 patients enrolled into the study. Eighty-four eligible patients were randomized, and 83 completed the study and were included in the final efficacy analysis. INTERVENTIONS: Following a two-to four-week washout period (baseline), patients were randomly allocated to receive felodipine ER 5 mg, amlodipine 5 mg or nifedipine GITS 30 mg for four weeks (low dose). All study patients had their daily dose doubled to felodipine ER 10 mg, amlodipine 10 mg or nifedipine GITS 60 mg for a further four weeks (high dose). MAIN RESULTS: Significant (P < 0.001) and similar changes from baseline in clinic BP were observed in all treatment groups for low and high doses. Ambulatory BP profiles showed comparable blood pressure reductions with felodipine ER and amlodipine, and a trend towards a lesser reduction with nifedipine GITS during 24 h, daytime and night-time periods. BP loads were similarly reduced with the three treatments. Trough to peak ratios (T:Ps) were calculated from 24 h ambulatory BP curves according to two different approaches: for diastolic and systolic BP, respectively, the global approach produced T:Ps of 0.49 and 0.50 with felodipine ER 5 mg; 0.50 and 0.34 with felodipine ER 10 mg; 0.70 and 0.60 with amlodipine 5 mg; 0.88 and 0.82 with amlodipine 10 mg; 0.65 and 0.55 with nifedipine GITS 30 mg; 0.68 and 0.53 with nifedipine GITS 60 mg. T:Ps in the individual approach were 0.07 and 0.10 with felodipine ER 5 mg; 0.23 and 0.31 with felodipine ER 10 mg; 0.22 and 0.31 with amlodipine 5 mg; 0.45 and 0.58 with amlodipine 10 mg; 0.27 and 0.31 with nifedipine GITS 30 mg; and 0.24 and 0.40 with nifedipine GITS 60 mg. CONCLUSION: There was no evidence in this study of a difference among felodipine ER, amlodipine and nifedipine GITS in lowering ambulatory or clinic BP. Treatment based on ambulatory BP may be preferable to treatment guided by T:Ps because ambulatory BP is firmly established as a predictor of cardiovascular risk. Furthermore, there is no consensus on how to calculate T:Ps, and different methods of calculation may give divergent results.     

Canadian collaboration networks: A comparative analysis of the natural sciences, social sciences and the humanities

Summary A basic dichotomy is generally made between publication practices in the natural sciences and engineering (NSE) on the one hand and social sciences and humanities (SSH) on the other. However, while researchers in the NSE share some common practices with researchers in SSH, the spectrum of practices is broader in the latter. Drawing on data from the CD-ROM versions of the Science Citation Index, Social Sciences Citation Index and the Arts & Humanities Citation Index from 1980 to 2002, this paper compares collaboration patterns in the SSH to those in the NSE. We show that, contrary to a widely held belief, researchers in the social sciences and the humanities do not form a homogeneous category. In fact, collaborative activities of researchers in the social sciences are more comparable to those of researchers in the NSE than in the humanities. Also, we see that language and geographical proximity influences the choice of collaborators in the SSH, but also in the NSE. This empirical analysis, which sheds a new light on the collaborative activities of researchers in the NSE compared to those in the SSH, may have policy implications as granting councils in these fields have a tendency to imitate programs developed for the NSE, without always taking into account the specificity of the humanities.     

Low-dose cyclosporine for the treatment of Crohn's disease. The Canadian Crohn's Relapse Prevention Trial Investigators

BACKGROUND: Long-term corticosteroid therapy for Crohn's disease is associated with important types of morbidity, such as osteoporosis. Safe and effective alternative treatments are required. Although a short-term benefit of cyclosporine in active Crohn's disease has been suggested, the long-term safety and efficacy of this treatment have not been established. METHODS: We conducted a randomized, double-blind, placebo-controlled evaluation of the effect of 18 months of low-dose cyclosporine treatment on the course of Crohn's disease. Adult patients whose disease had been active within the previous two years were randomly assigned to receive cyclosporine (151 patients) or placebo (154 patients) in addition to their usual therapy. Randomization was stratified according to center and score on the Crohn's Disease Activity Index (193 patients had scores of 150 or less, and 112 had scores greater than 150). The primary outcome measure was clinically important worsening of Crohn's disease, defined as a 100-point increase in the Crohn's Disease Activity Index from the patient's base-line value. Secondary outcomes were the use of prednisone and 5-amino-salicylates, mean score on the Crohn's Disease Activity Index and mean quality-of-life score, and the need for surgery. RESULTS: The condition of more patients worsened with cyclosporine than with placebo (91 of 151, or 60.3 percent, vs. 80 of 154, or 51.9 percent; P = 0.10). The median time to worsening of disease in patients receiving cyclosporine was 338 days, as compared with 492 days in patients receiving placebo (P = 0.25; relative risk, 1.22; 95 percent confidence interval, 0.86 to 1.72). Analyses of the mean Crohn's Disease Activity Index and quality-of-life scores and of the use of prednisone and 5-aminosalicylates also failed to demonstrate benefit. CONCLUSIONS: In our patient population, the addition of low-dose cyclosporine to conventional treatment for Crohn's disease did not improve symptoms or reduce requirements for other forms of therapy.