Double clad tubular anti-resonant hollow core fiber for nonlinear microendoscopy.

We report the fabrication and characterization of the first double clad tubular anti-resonant hollow core fiber. It allows to deliver ultrashort pulses without temporal nor spectral distortions in the 700-1000 nm wavelength range and to efficiently collect scattered light in a high numerical aperture double clad. The output fiber mode is shaped with a silica microsphere generating a photonic nanojet, making it well suitable for nonlinear microendoscopy application. Additionally, we provide an open access software allowing to find optimal drawing parameters for the fabrication of tubular hollow core fibers.

Returning to care after incarceration with HIV: the French Guianese experience.

BACKGROUND: HIV prevalence in correctional facilities may be 2 to 10 times higher than in the general adult population. Antiretroviral therapy (ART) interruption is frequent after an incarceration. This, in combination with post-release high-risk behaviors, may have detrimental consequences on the epidemic. Although return to care after release from correctional facilities has been described in many North American settings, data from South America seemed scarce. French Guiana is the only French territory located in South America. In 2014, HIV prevalence was estimated at 1.2% among pregnant women and oscillated around 4% in the only correctional facility. METHOD: HIV-infected adults released from the French Guiana correctional facility between 2007 and 2013 were included in a retrospective cohort survey. The first objective was to describe the cascade of care in the 4 years following release. The secondary objectives were to describe contacts with care and to identify factors associated with return to HIV care, 1 year after release. RESULTS: We included 147 people, mostly males (81.6%). The median time before the first ambulatory consultation was 1.8 months. Within 1 year after release, 27.9% came for unscheduled emergency consultations, 22.4% were hospitalized. Within 4 years after release, 40.0-46.5% were in care, 22.4% archieved virological success. Being on ART when incarcerated was associated with HIV care (aIRR: 2.0, CI: 1.2-3.0), whereas being HIV-diagnosed during the last incarceration was associated with poor follow-up (aIRR: 0.3, CI: 0.1-0.9). CONCLUSION: The risk of HIV-follow-up interruption is high, after an incarceration with HIV. ART supply should be sufficient to cover the timespan following release, several months if possible. Those not on ART at the time of incarceration may require special attention, especially those newly HIV-diagnosed while in custody. Comprehensive programs are necessary to support ex-offenders to stay on ART after incarceration.

Modelling and control of potable water chlorination.

The Umgeni Water Wiggins water treatment plant feeds the southern areas of Durban in South Africa and has a maximum treatment capacity of about 350 Ml/d. Two interconnected reservoirs at this facility hold treated water before it enters the distribution network. Because of the variable demand, the reservoir levels and residence times undergo considerable variation. This has a strong influence on the free chlorine concentration in the water leaving the reservoir, which should be 0.8 to 1.2 mg/l, to ensure an adequate disinfection potential within the network. This paper describes a model which accounts for the observed variations of chlorine concentration, and will form the basis of a predictive controller for the chlorine concentration in the outlet.