ABSTRACT
We present an ultra-wide band photonic integrated 4×4 polymer cross-bar switch matrix based on total internal reflection and the thermo-optic effect. The photonic integrated polymer switch owns low insertion loss, low power consumption, wavelength, and polarization-independent operation for all switching paths. The experimental results show ultra-wide band (O- to L-band) operation with fiber-to-fiber insertion losses ranging from -3.7 to -6.5dB, 0.1 to 0.6 dB polarization-dependent losses, switching the on-off ratio above 36 dB on average, and 25 mW power consumption per path. Error-free operation with a power penalty <0.2dB at 1 E-9 bit error rate (BER) for ultra-wide band non-return-to-zero on-off keying (NRZ-OOK) wavelength-division multiplexing (WDM) switched signals at 10, 25, 40, and 50 Gbit/s, and 510 Gbps dual polarization 64-QAM switched data with a negligible penalty were measured.
ABSTRACT
People living with human immunodeficiency virus (HIV) are more likely to develop urinary tract infections (UTI) due to the suppression of their immunity. The aim of this study was to determine the prevalence, risk factors of UTI, and drug susceptibility pattern of bacteria isolated among peoples infected with HIV. A hospital-based cross-sectional study was conducted among 224 HIV positive individuals attending Hawassa University Comprehensive Specialized Hospital (HUCSH) from September 17 to November 16, 2018. Midstream urine was collected from all study participants and inoculated on to Blood and MacConkey agar. Bacterial isolates were characterized by Gram stain and standard biochemical tests. Kirby-Bauer method was used for antimicrobial susceptibility testing. Sociodemographic and clinical data were collected by a semi-structured questionnaire. Data were analyzed using SPSS version 20. A bivariate and a multivariable regression model were employed to determine the association between dependent and independent variables. From the total 224 study participants, 23 (10.3%) (95% CI 6.7-14.7) had culture-confirmed UTIs. The distributions of the bacteria were as follows: Escherichia coli 16 (69.6%), Staphylococcus aureus 2 (8.7%), Klebsiella pneumoniae 2 (8.7%), Enterobacter aerogenes 2 (8.7%) and Pseudomonas species 1 (4.3%). UTI prevalence was also high among study participants with a previous history of UTI and CD4+ count < 200/mm3. Female study participants were about five times more likely to have UTI (AOR 5.3, 95% CI 1.5-19.2). Ninety-three percent of bacteria isolated were susceptible to nitrofurantoin, ceftriaxone, and gentamycin; 87.5% were susceptible to meropenem and norfloxacin; whereas 93.8%, 68.8%, and 62.5% of isolates were resistant to ampicillin, tetracycline, and cotrimoxazole respectively. Multidrug resistance (MDR) was seen in 18 (78.3%) of bacterial isolates.
