Controlling pulse propagation in optical fibers through nonlinearity and dispersion management

In case of the nonlinear Schr\"odinger equation with designed group velocity dispersion, variable nonlinearity and gain/loss; we analytically demonstrate the phenomenon of chirp reversal crucial for pulse reproduction. Two different scenarios are exhibited, where the pulses experience identical dispersion profiles, but show entirely different propagation behavior. Exact expressions for dynamical quasi-solitons and soliton bound-states relevant for fiber communication are also exhibited.Comment: 4 pages, 5 eps figure

Molecular detection and genotyping of Chlamydia trachomatis circulating in women of Western Cameroon: a cross-sectional study

Background: In Cameroon, C. trachomatis screening is not routinely practiced, and its epidemiology is still unexplored. The present study aimed to determine the prevalence of C. trachomatis infection, its risk factors and the genotypes circulating in the West Cameroon region.Methods: A cross-sectional study was carried out amongst patients in five district hospitals in the West region of Cameroon. Endocervical samples were collected from women visiting the hospitals forantenatal, prenuptial and contraception consultations and at least 18 years old, sexually active, and non-menstruating. The molecular detection of C. trachomatis was performed using conventional polymerase chain reaction (PCR) followed by sequencing of the ompA gene.Results: The prevalence of C. trachomatis infection was determined to be 11.47%. Having sex for the first time between the ages of 15 and 17 (OR=1.683, 95% CI: 1.1-2.5), non-usage of condom (OR=1.622, 95% CI: 1.2-2.1), being single (OR=1.263, 95% CI: 1.0-1.5) and age range 18-30 years (OR=1.426, 95% CI: 1.1-1.8) were risk factors for C. trachomatis infection. Three genotypes of C. trachomatis circulated in West Cameroon viz. D (49%), E (29.4%) and G (21.6%).Conclusions: This study revealed that, three genotypes; D (dominant), E and G were identified circulating in the population of the study area. This information may be important for controlling the dissemination of C. trachomatis infection in West Cameroon as well as strategizing the therapeutic approach. </jats:p

Mitoxantrone-Induced Cardiotoxicity in Acute Myeloid Leukemia-A Velocity Vector Imaging Analysis

BACKGROUND: The purpose of this investigation was to: (1) determine incidence and predictors of mitoxantrone-induced early cardiotoxicity and (2) study left ventricular mechanics before and after receiving mitoxantrone. METHOD AND RESULTS: We retrospectively analyzed 80 subjects diagnosed with acute myeloid leukemia (AML) who underwent chemotherapy with bolus high-dose mitoxantrone. Echocardiographic measurements were taken at baseline and at a median interval of 55 days after receiving mitoxantrone. Thirty-five (44%) of the patients developed clinically defined early cardiotoxicity, 29 (36%) of which developed heart failure. There was a significant decrease in the ejection fraction (EF) not only in the cardiotoxicity group (17.6 +/- 14.8%, P < 0.001) but also in the noncardiotoxicity group (5.3 +/- 8.4%, P < 0.001). Decrease in global longitudinal strain (GLS) (-3.7 +/- 4.5, P < 0.001 vs. -2.4 +/- 4.3, P = 0.01) and global circumferential strain (GCS) (-5.6 +/- 9, P = 0.003 vs. -5.3 +/- 8.7, P < 0.001) was significant in both the cardiotoxicity and noncardiotoxicity group, respectively. A multivariate model including baseline left ventricular end-systolic diameter, baseline pre-E/A ratio, and baseline pre-E/e' ratio was found to be the best-fitted model for prediction of mitoxantrone-induced early clinical cardiotoxicity. CONCLUSION: High-dose mitoxantrone therapy is associated with an excellent remission rate but with a significantly increased risk of clinical and subclinical early cardiotoxicity and heart failure. Mitoxantrone-induced systolic dysfunction is evident from reduction in EF, increase in Tei index, and significant reduction in GLS and GCS. Baseline impaired ventricular relaxation evident from higher E/e' ratio and lower E/A ratio independently predicts increased risk of mitoxantrone-induced early cardiotoxicity