III-V-on-silicon anti-colliding pulse-type mode-locked laser

An anti-colliding pulse-type III–V-on-silicon passively mode-locked laser is presented for the first time based on a III–V-on-silicon distributed Bragg reflector as outcoupling mirror implemented partially underneath the III–V saturable absorber. Passive mode-locking at 4.83 GHz repetition rate generating 3 ps pulses is demonstrated. The generated fundamental RF tone shows a 1.7 kHz 3 dB linewidth. Over 9 mW waveguide coupled output power is demonstrated

Recent advances in the photonic integration of mode-locked laser diodes

Mode-locked fiber and solid state lasers have played an essential role in several scientific and technological developments. The integration of mode-locked lasers on chips could enable their use in a wide range of applications. The advancement of semiconductor mode-locked laser diodes has been going on for several decades, but has recently seen the development of novel devices based on generic InP and III-V-on-silicon photonic integration platforms. These photonic integration platforms enable the use of standardized components and low-loss waveguides within the laser cavity, allowing for the design of advanced extended cavities. In this manuscript we give a review of these novel devices and compare their performance

Effect of HSV-2 Suppressive Therapy on Genital Tract HIV-1 RNA Shedding among Women on HAART: A Pilot Randomized Controlled Trial

Background. The role of suppressive HSV therapy in women coinfected with HSV-2 and HIV-1 taking highly active antiretroviral therapy (HAART) is unclear. Methods. 60 women with HIV-1/HSV-2 coinfection on HAART with plasma HIV-1 viral load (PVL) ≤75 copies/mL were randomized to receive acyclovir (N = 30) or no acyclovir (N = 30). PVL, genital tract (GT) HIV-1, and GT HSV were measured every 4 weeks for one year. Results. Detection of GT HIV-1 was not significantly different in the two arms (OR 1.23, P = 0.67), although this pilot study was underpowered to detect this difference. When PVL was undetectable, the odds of detecting GT HIV were 0.4 times smaller in the acyclovir arm than in the control arm, though this was not statistically significant (P = 0.07). The odds of detecting GT HSV DNA in women receiving acyclovir were significantly lower than in women in the control group, OR 0.38, P < 0.05. Conclusions. Chronic suppressive therapy with acyclovir in HIV-1/HSV-2-positive women on HAART significantly reduces asymptomatic GT HSV shedding, though not GT HIV shedding or PVL. PVL was strongly associated with GT HIV shedding, reinforcing the importance of HAART in decreasing HIV sexual transmission

Vaginal flora morphotypic profiles and assessment of bacterial vaginosis in women at risk for HIV infection.

Specific morphotypic profiles of normal and abnormal vaginal flora, including bacterial vaginosis (BV), were characterized. A prospective study of 350 women yielded concurrent Gram-stain data and clinical assessment (n = 3455 visits). Microbiological profiles were constructed by Gram stain. Eight profile definitions were based on dichotomizing the levels of Lactobacillus, Gardnerella, and curved, Gram-negative bacillus (Mobiluncus) morphotypes. Of these, two were rare, and the other six demonstrated a graded association with the clinical components of BV. The proposed profiles from the Gram stain reflect the morphotypic categories describing vaginal flora that may enable clearer elucidation of gynecologic and obstetric outcomes in various populations

Frequency comb generation in III-V-on-silicon photonic integrated circuits

We present our recent work on the realization of III-V-on-silicon mode-locked lasers and integrated nonlinear waveguides for the realization of integrated frequency combs

HIV-1 RNA genital tract shedding after cryotherapy for visual inspection with acetic acid-positive cervical lesions in western Kenya

Objectives: To quantify genital tract HIV-1 RNA (GT-HIV RNA) shedding among women living with HIV (WLHIV) before and after cryotherapy treatment for visual inspection with acetic acid (VIA) positive cervical lesions. Methods:We conducted a prospective, longitudinal study of 39 WLHIV on antiretroviral treatment (ART) undergoing cryotherapy for VIA positive lesions in Kenya from 2015-2017. Eligibility for cryotherapy were lesions that covered Results: Detectable GT-HIV RNA was found in 4/39 (10%) participants pre-cryotherapy, 1/30 (3.3%) and 3/26 (11.5%) participants at the 2- and 8-weeks post-cryotherapy, respectively. Only 6/39 (13%) participants had detectable GT-HIV RNA at any point during the study. 2/6 had recent high PVL (range: 49,124-150,695 copies/mL) within 3 months of starting the study and detectable GT-HIV RNA at follow-up visits. 4/6 had undetectable recent PVL within 3-11 months of the study but each had detectable GT-HIV RNA pre-cryotherapy. The mean GT-HIV RNA among 4/39 WLHIV with shedding at pre-cryotherapy was 43,109 (range: 21,812-73,625) copies/mL. Only one participant had GT-HIV RNA (73,125 copies/mL) at 2-weeks post-cryotherapy (N=30); she had no shedding pre-cryotherapy but had a PVL of 49,124 copies/mL 3 months before the study. The mean GT-HIV RNA at 8-weeks post-cryotherapy (N=26) was 44,668 (range: 21,256-64,812) copies/mL among three participants. One of the 3 had high PVL of 150,695 copies/mL 3 months prior to cryotherapy while 2/3 had GT-HIV RNA shedding at baseline despite undetectable most recent PVL. However, their undetectable PVL was 8-11 months prior to cryotherapy which may not accurately reflect PVL at baseline. Conclusions: The majority of GT-HIV RNA shedding was detected before cryotherapy. This finding suggests that cryotherapy was not the primary cause of GT-HIV RNA shedding. Non-adherence to ART might have played a major role. The small sample size and failure to perform paired GT-HIV RNA and PVL tests at each visit are limitations of the study. Further research on the effect of cryotherapy on GT-HIV RNA shedding in ART non-adherent compared to ART-adherent WLHIV is needed

Bacterial Vaginosis and the Natural History of Human Papillomavirus

Objective. To evaluate associations between common vaginal infections and human papillomavirus (HPV). Study Design. Data from up to 15 visits on 756 HIV-infected women and 380 high-risk HIV-uninfected women enrolled in the HIV Epidemiology Research Study (HERS) were evaluated for associations of bacterial vaginosis, trichomoniasis, and vaginal Candida colonization with prevalent HPV, incident HPV, and clearance of HPV in multivariate analysis. Results. Bacterial vaginosis (BV) was associated with increased odds for prevalent (aOR = 1.14, 95% CI: 1.04, 1.26) and incident (aOR = 1.24, 95% CI: 1.04, 1.47) HPV and with delayed clearance of infection (aHR = 0.84, 95% CI: 0.72, 0.97). Whereas BV at the preceding or current visit was associated with incident HPV, in an alternate model for the outcome of incident BV, HPV at the current, but not preceding, visit was associated with incident BV. Conclusion. These findings underscore the importance of prevention and successful treatment of bacterial vaginosis

Association between Semen Exposure and Incident Bacterial Vaginosis

Objective. To identify correlates of incident bacterial vaginosis (BV) diagnosed with Nugent scoring among high-risk women. Study Design. We conducted both cohort and case-crossover analyses, stratified by HIV infection status, based on 871 HIV-infected and 439 HIV-uninfected participants in the HIV Epidemiology Research Study, conducted in 4 US sites in 1993–2000. Results. BV incidence was 21% and 19% among HIV-infected and -uninfected women, respectively. Fewer correlates of BV were found with case-crossover than with cohort design. Reporting frequent coitus (regardless of consistency of condom use) was correlated with BV in cohort analyses but not in case-crossover analyses. The sole correlate of BV in both types of analyses was the detection of spermatozoa on Gram stain, which is a marker of semen exposure. Conclusion. The inconsistent association between condom use and BV in prior studies could be from reporting bias. We found evidence of a relationship between semen exposure and incident BV

Accountability, Strategy, and International Non-Governmental Organizations

Increased prominence and greater influence expose international non-governmental development and environmental organizations (INGOs) to increased demands for accountability from a wide variety of stakeholdersdonors, beneficiaries, staffs, and partners among others. This paper focuses on developing the concept of INGO accountability, first as an abstract concept and then as a strategic idea with very different implications for different INGO strategies. We examine those implications for INGOs that emphasize service delivery, capacity-building, and policy influence. We propose that INGOs committed to service delivery may owe more accountability to donors and service regulators; capacity-building INGOs may be particularly obligated to clients whose capacities are being enhanced; and policy influence INGOs may be especially accountable to political constituencies and to influence targets. INGOs that are expanding their activities to include new initiatives may need to reorganize their accountability systems to implement their strategies effectively. This publication is Hauser Center Working Paper No. 7. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers