Two-Channel OTDM System for Data-Center Interconnects: A Review.

It has been proposed to implement the >100 Gb/s data-center interconnects using a two-channel optical time-division multiplexed system with multilevel pulse-amplitude modulation. Unlike the conventional four-channel optical time-division multiplexed system which requires an expensive narrow pulse, the two-channel system can be implemented cost-effectively using a wide pulse (which can be simply generated using a single modulator). The two-channel system is expected to be practically available using an integrated transmitter in a chip due to the recent advances in photonics-integrated circuits. This paper reviews the current stage of research on a two-channel optical time-division multiplexed system and discusses possible research directions. Furthermore, it has been demonstrated that 200 Gb/s signals can be generated by using modulators with only 17.2 GHz bandwidth. Therefore, the use of the phase-alternating pulse can make the multiplexed signal robust to chromatic dispersion, enabling the 200 Gb/s 4-level pulse-amplitude-modulated signal to be transmitted over 1.9 km of standard single-mode fiber.

Chemoresistive Sensor Readout Circuit Design for Detecting Gases with Slow Response Time Characteristics.

Based on an analysis of the signal characteristics of gas sensors, this work presents a chemoresistive sensor readout circuit design for detecting gases with slow response time characteristics. The proposed readout circuit directly generates a reference voltage corresponding to the initial value of the gas sensor and extracts only the amount of gas concentration change in the sensor. Because the proposed readout circuit can adaptively regenerate the suitable reference voltage under various changing ambient conditions, it can alleviate the variation in output values at the same gas concentration caused by non-uniformities among gas sensors. Furthermore, this readout circuit effectively eliminates the initial value shifts due to the poor reproducibility of the gas sensor itself without requiring complex digital signal calibrations. This work focuses on a commercially viable readout circuit structure that can effectively obtain slow response gas information without requiring a large capacitor. The proposed readout circuit operation was verified by simulations using spectre in cadence simulation software. It was then implemented on a printed circuit board with discrete components to confirm the effectiveness with existing gas sensor systems and its commercial viability.

Comparison of Antimicrobial Susceptibility Test Results of Disk Diffusion, Gradient Strip, and Automated Dilution with Broth Microdilution for Piperacillin-Tazobactam.

In the treatment of septic patients, the prediction of a pathogen's susceptibility to piperacillin-tazobactam can be crucial. Commercial tests are available to measure the pathogen's susceptibility to piperacillin-tazobactam, but there is conflicting evidence regarding their accuracy. Therefore, this study compared the accuracy of disk diffusion, gradient strip, and automated dilution with the accepted standard broth microdilution. Testing was performed on 150 blood culture isolates from hospitalized patients at the University Hospital Bonn. The most recent Escherichia coli (n = 50), Klebsiella pneumoniae (n = 50), and Pseudomonas aeruginosa (n = 50) isolates were chosen. All measurements were performed strictly according to the manufacturer's instructions. Minimal inhibitory concentrations were primarily interpreted based on EUCAST (European Committee on Antimicrobial Susceptibility Testing) 8.1 and supplementarily based on CLSI (Clinical and Laboratory Standards Institute) 28th. The results of automated dilution showed a categorical agreement of 93.3% and presented five minor errors, four major errors, and one very major error. The results for gradient strip and disk diffusion were similar, except for the three additional major errors in the gradient strip and two additional very major errors in disk diffusion. Most of the major errors and very major errors were associated with P. aeruginosa. In conclusion, there was no relevant difference in accuracy between the three compared tests. Their overall categorical agreement ranged from 90.7% to 93.3% and was therefore at the lower end of the threshold. The possibly increased error rate for P. aeruginosa could be relevant in the preparation of empirical antibiotic guidelines and the treatment of septic patients. Universal Trial Number: U1111-1224-0035.

A High-Multi Target Resolution Focal Plane Array-Based Laser Detection and Ranging Sensor.

This paper introduces a digital-assisted multiple echo detection scheme, which utilizes the waste time of the full serial data readout period in a focal plane array (FPA)-based laser detection and ranging (LADAR) receiver. With the support of an external digital signal processor (DSP) and additional analog memory inserted into the receiver, the proposed readout scheme can effectively enhance multi-target resolution (MTR) three times higher than the conventional FPA-based LADAR, while maintaining low power consumption and a small area. A prototype chip was fabricated in a 0.18-µm CMOS process with an 8 × 8 FPA configuration, where each single receiver pixel occupied an area of 100 µm × 100 µm. The single receiver achieved an MTR of 20 ns with 7.47 mW power dissipation, an input referred noise current of 4.48 pA/√Hz with a bandwidth 530 MHz, a minimum detectable signal (MDS) of 340 nA, a maximum walk error of 2.2 ns, and a maximum non-linearity of 0.05% among the captured multiple echo images.

Urinary continence after radical prostatectomy: predictive factors of recovery after 1 year of surgery.

OBJECTIVES: To evaluate the clinical prognosis of incontinence and to determine the predictors for further recovery of urinary continence in patients not achieving urinary continence within 1 year after radical prostatectomy. METHODS: A total of 708 patients were evaluated regarding urinary continence status at 1 year after surgery from a prospectively maintained radical prostatectomy database. Of these, 73 (10.3%) did not recover urinary continence within 1 year after surgery. For these patients, incontinence status and the number of pads for urinary control were assessed serially. RESULTS: In 708 patients, factors associated with the recovery of urinary continence within 1 year after radical prostatectomy were membranous urethral length, prostatic apex shape and patient age. Among 73 patients with urinary incontinence, 41 (56.2%) achieved urinary continence with a mean time of 15.4 months subsequent to the first year after radical prostatectomy (baseline). A younger age at surgery (P = 0.027) and one pad being required (vs ≥2 pads) at baseline (P = 0.046) were identified as independent factors for achievement of urinary continence within a further 2 years. Only the number of pads was a significant factor for further recovery of urinary continence in the longer follow up (hazard ratio 0.36, P = 0.029). CONCLUSION: Compared with factors related to the prostate or membranous urethra, patient age and severity of incontinence at 1 year after radical prostatectomy are more strongly related to the recovery of urinary continence later than 1 year after surgery. These findings might help to decide whether a definite treatment is required for persistent incontinence beyond 1 year after radical prostatectomy.

Prevalence and Clinical Features of Detrusor Underactivity among Elderly with Lower Urinary Tract Symptoms: A Comparison between Men and Women.

PURPOSE: To identify the prevalence and clinical features of detrusor underactivity (DU) in elderly men and women presenting with lower urinary tract symptoms (LUTS). MATERIALS AND METHODS: We reviewed 1,179 patients aged over 65 years who had undergone a urodynamic study for LUTS with no neurological or anatomical conditions. DU was defined as a bladder contractility index <100 and a maximal flow rate (Qmax) ≤12 ml/s combined with a detrusor pressure at Qmax ≤10 cmH(2)O for men and women, respectively. RESULTS: Of the patients, 40.2% of men and 13.3% of women were classified as having DU (p<0.001). Types of clinical symptoms were not significantly different between patients with and without DU. In men, whereas the prevalence of bladder outlet obstruction (BOO) was constant across the age spectrum, the prevalence of DU and detrusor overactivity (DO) increased with age, and 46.5% of men with DU also had DO or BOO. In women, the prevalence of DU also increased with age, and the trend was more remarkable in women aged over 70 years. DU was accompanied by DO or urodynamic stress urinary incontinence (USUI) in 72.6% of the women with DU. Women with DU were found to have lower cystometric capacity and exhibited a greater incidence of reduced compliance than did women without DU. CONCLUSIONS: DU was a common mechanism underlying LUTS in the elderly population, especially in men. One half of the men and three quarters of the women with DU also had other pathologies such as DO, BOO, or USUI.

Women with pure stress urinary incontinence symptoms assessed by the initial standard evaluation including measurement of post-void residual volume and a stress test: are urodynamic studies still needed?

AIMS: The significance of preoperative urodynamic studies in women with a "clinically-defined pure stress urinary incontinence (SUI) symptom" has been debated in recent years. We evaluated changes of reliability of pure SUI symptoms for prediction of pure urodynamic SUI (USUI) when the assessment of post-void residual (PVR) volume and a stress test, designated as the initial standard evaluation in the NICE and AUA guidelines, were added to the process for the diagnosis of pure SUI symptoms. METHODS: We reviewed records of 1,019 women aged 30-80 who underwent urodynamic study for incontinence. Criteria for pure SUI symptoms were defined as absence of overactive bladder symptoms and voiding difficulties based on a frequency-volume chart and AUA Symptom Index. We then added assessment of PVR volume and a stress test to the process for clinical diagnosis. RESULTS: Of subjects, 211 (20.7%) could be classified as having a pure SUI symptom. Of these, only 167 (79.1%) had pure USUI and 33 (15.7%) had detrusor overactivity. Eight (3.8%) had detrusor underactivity/bladder outlet obstruction. Sensitivity and specificity of pure SUI symptoms for pure USUI were 28.6% and 89.9%. Addition of assessment of PVR volume and a stress test resulted in an increase of predictive accuracy of only 3.6%. CONCLUSIONS: As one-fifth of women with pure SUI symptoms exhibit the pathophysiologies that could affect the surgical outcomes despite additional use of PVR assessment and a stress test in the clinical diagnostic process, urodynamic evaluation is considered necessary before anti-incontinence surgery in this population.