Implementing a group-based multi-component early child development intervention through the government health system in rural Bangladesh: A feasibility study.

Children in low- and middle-income countries face an increased risk of impaired cognitive development due to contaminated environments, poor nutrition, and inadequate responsive stimulation from caregivers. Implementing multi-component, community-level interventions may reduce these risks; however, there is little evidence supporting implementation of these interventions at scale. We assessed the feasibility of implementing a group-based intervention that included responsive stimulation, maternal and child nutrition, water and sanitation, and childhood lead exposure prevention through the government health system in Chatmohar, Bangladesh. After implementation, we conducted 17 in-depth interviews with frontline health service providers and 12 key informant interviews with their supervisors and managers to explore the facilitators and difficulties implementing such a complex programme within the health system. Factors facilitating implementation included: high quality training and skill level of providers, support from community members, family, and supervisors, positive relationships between providers and participants, and provision of children's toys and books free of cost. Difficulties included increased workload of the providers, complicated group-based yet stage-specific delivery where providers had to manage a large group of mother-child dyads representing many different child age-groups at once, and logistics difficulties in providing toys and books through a centralised health system process. Key informants made suggestions to ensure effective government-level scale-up including engaging relevant NGOs as partners, identifying feasible ways to make toys available, and offering providers meaningful even if non-monetary rewards. These findings can be used to shape the design and delivery of multi-component child development interventions to be delivered through the health system.

Feasibility and acceptability of home-based neonatal hyperbilirubinemia screening by community health workers using transcutaneous bilimeters in Bangladesh.

BACKGROUND: Universal screening for neonatal hyperbilirubinemia risk assessment is recommended by the American Academy of Pediatrics to reduce related morbidity. In Bangladesh and in many low- and middle-income countries, there is no screening for neonatal hyperbilirubinemia. Furthermore, neonatal hyperbilirubinemia may not be recognized as a medically significant condition by caregivers and community members. We aimed to evaluate the acceptability and operational feasibility of community health worker (CHW)-led, home-based, non-invasive neonatal hyperbilirubinemia screening using a transcutaneous bilimeter in Shakhipur, a rural subdistrict in Bangladesh. METHODS: We employed a two-step process. In the formative phase, we conducted eight focus group discussions with parents and grandparents of infants and eight key informant interviews with public and private healthcare providers and managers to explore their current knowledge, perceptions, practices, and challenges regarding identification and management of neonatal hyperbilirubinemia. Next, we piloted a prenatal sensitization intervention and home-based screening by CHWs using transcutaneous bilimeters and evaluated the acceptability and operational feasibility of this approach through focus group discussions and key informant interviews with parents, grandparents and CHWs. RESULTS: Formative findings identified misconceptions regarding neonatal hyperbilirubinemia causes and health risks among caregivers in rural Bangladesh. CHWs were comfortable with adoption, maintenance and use of the device in routine home visits. Transcutaneous bilimeter-based screening was also widely accepted by caregivers and family members due to its noninvasive technique and immediate display of findings at home. Prenatal sensitization of caregivers and family members helped to create a supportive environment in the family and empowered mothers as primary caregivers. CONCLUSION: Adopting household neonatal hyperbilirubinemia screening in the postnatal period by CHWs using a transcutaneous bilimeter is an acceptable approach by both CHWs and families and may increase rates of screening to prevent morbidity and mortality.

Integrated femtosecond pulse generator on thin-film lithium niobate.

Integrated femtosecond pulse and frequency comb sources are critical components for a wide range of applications, including optical atomic clocks1, microwave photonics2, spectroscopy3, optical wave synthesis4, frequency conversion5, communications6, lidar7, optical computing8 and astronomy9. The leading approaches for on-chip pulse generation rely on mode-locking inside microresonators with either third-order nonlinearity10 or with semiconductor gain11,12. These approaches, however, are limited in noise performance, wavelength and repetition rate tunability 10,13. Alternatively, subpicosecond pulses can be synthesized without mode-locking, by modulating a continuous-wave single-frequency laser using electro-optic modulators1,14-17. Here we demonstrate a chip-scale femtosecond pulse source implemented on an integrated lithium niobate photonic platform18, using cascaded low-loss electro-optic amplitude and phase modulators and chirped Bragg grating, forming a time-lens system19. The device is driven by a continuous-wave distributed feedback laser chip and controlled by a single continuous-wave microwave source without the need for any stabilization or locking. We measure femtosecond pulse trains (520-femtosecond duration) with a 30-gigahertz repetition rate, flat-top optical spectra with a 10-decibel optical bandwidth of 12.6 nanometres, individual comb-line powers above 0.1 milliwatts, and pulse energies of 0.54 picojoules. Our results represent a tunable, robust and low-cost integrated pulsed light source with continuous-wave-to-pulse conversion efficiencies an order of magnitude higher than those achieved with previous integrated sources. Our pulse generator may find applications in fields such as ultrafast optical measurement19,20 or networks of distributed quantum computers21,22.

Time to Scale Up Preexposure Prophylaxis Beyond the Highest-Risk Populations? Modeling Insights From High-Risk Women in Sub-Saharan Africa.

OBJECTIVES: New HIV infections remain higher in women than men in sub-Saharan Africa. Preexposure prophylaxis (PrEP) is an effective HIV prevention measure, currently prioritized for those at highest risk, such as female sex workers (FSWs), for whom it is most cost-effective. However, the greatest number of HIV infections in sub-Saharan Africa occurs in women in the general population. As countries consider wider PrEP scale-up, there is a need to weigh the population-level impact, cost, and relative cost-effectiveness to inform priority setting. METHODS: We developed mathematical models of HIV risk to women and derived tools to highlight key considerations for PrEP programming. The models were fitted to South Africa, Zimbabwe, and Kenya, spanning a range of HIV burden in sub-Saharan Africa. The impact, cost, and cost-effectiveness of PrEP scale-up for adolescent girls and young women (AGYW), women 25 to 34 years old, and women 35 to 49 years old were assessed, accounting for differences in population sizes and the low program retention levels reported in demonstration projects. RESULTS: Preexposure prophylaxis could avert substantially more infections a year among women in general population than among FSW. The greatest number of infections could be averted annually among AGYW in South Africa (24-fold that for FSW). In Zimbabwe, the greatest number of infections could be averted among women 25 to 34 years old (8-fold that for FSW); and in Kenya, similarly between AGYW and women 25 to 34 years old (3-fold that for FSW). However, the unit costs of PrEP delivery for AGYW, women 25 to 34 years old, and women 35 to 49 years old would have to reduce considerably (by 70.8%-91.0% across scenarios) for scale-up to these populations to be as cost-effective as for FSW. CONCLUSIONS: Preexposure prophylaxis has the potential to substantially reduce new HIV infections in HIV-endemic countries in sub-Saharan Africa. This will necessitate PrEP being made widely available beyond those at highest individual risk and continued integration into a range of national services and at community level to significantly bring down the costs and improve cost-effectiveness.

Oral preexposure prophylaxis continuation, measurement and reporting.

OBJECTIVE: The aim of this study was to appropriately plan for rollout and monitor impact of oral preexposure prophylaxis (PrEP). It is important to understand PrEP continuation and come to a consensus on how best to measure PrEP continuation. This study reviews data on PrEP continuation to document how it is reported, and to compare continuation over time and across populations. DESIGN: A systematic review and meta-analysis. METHODS: We searched MEDLINE, Embase and Global Health and reviewed abstracts from HIV conferences from 2017 to 2018 for studies reporting primary data on PrEP continuation. Findings were summarized along a PrEP cascade and continuation was presented by population at months 1, 6 and 12, with random-effects meta-analysis. RESULTS: Of 2578 articles and 596 abstracts identified, 41 studies were eligible covering 22 034 individuals. Continuation data were measured and reported inconsistently. Results showed high discontinuation at month 1 and persistent discontinuation at later time points in many studies. Pooled continuation estimates were 66% at month 1 [n = 5348; 95% confidence interval (95% CI): 48-82], 63% at month 6 (n = 13 629; 95% CI: 48-77) and 71% at month 12 (n = 14 933; 95% CI: 60-81; higher estimate than previous timepoints due to inclusion of different studies). Adequate data were not available to reliably compare estimates across populations. CONCLUSION: This review found that discontinuation at one month was high, suggesting PrEP initiations may be a poor measure of effectiveness. Continuation declined further over time in many studies, indicating existing cross-sectional indicators may not be adequate to understand PrEP use patterns. Studies do not measure continuation consistently, and consensus is needed.

Is modelling complexity always needed? Insights from modelling PrEP introduction in South Africa.

BACKGROUND: Mathematical models can be powerful policymaking tools. Simple, static models are user-friendly for policymakers. More complex, dynamic models account for time-dependent changes but are complicated to understand and produce. Under which conditions are static models adequate? We compare static and dynamic model predictions of whether behavioural disinhibition could undermine the impact of HIV pre-exposure prophylaxis (PrEP) provision to female sex workers in South Africa. METHODS: A static model of HIV risk was developed and adapted into a dynamic model. Both models were used to estimate the possible reduction in condom use, following PrEP introduction, without increasing HIV risk. The results were compared over a 20-year time horizon, in two contexts: at epidemic equilibrium and during an increasing epidemic. RESULTS: Over time horizons of up to 5 years, the models are consistent. Over longer timeframes, the static model overstates the tolerated reduction in condom use where initial condom use is reasonably high ($\ge$50%) and/or PrEP effectiveness is low ($\le$45%), especially during an increasing epidemic. CONCLUSIONS: Static models can provide useful deductions to guide policymaking around the introduction of a new HIV intervention over short-medium time horizons of up to 5 years. Over longer timeframes, static models may not sufficiently emphasise situations of programmatic importance, especially where underlying epidemics are still increasing.

Assessment of endocrine disruptor effects of levonorgestrel and its photoproducts: Environmental implications of released fractions after their photocatalytic removal.

The presence of levonorgestrel (LNG) in water bodies via direct discharge and human excretion has been reported worldwide, but its effects on the reproduction of aquatic species and humans are still unknown. Owing to its recalcitrant properties, LNG is not completely removed during wastewater treatment plants, and many species may be exposed to low traces of this compound from discharged effluents. Thus, in this study, a photocatalytic process for removing LNG along with screening of endocrine disruptor effects for risk assessment was applied. Although the removal rate of LNG by ultraviolet C (UV-C) radiation was >90%, reproductive toxicity testing using the BeWo cell line exposed to LNG and its degraded fraction showed the reduced production of basal human chorionic gonadotropin hormone (ß-hCG) by more than 73%, from 8.90 mIU mL-1 to <2.39 mIU mL-1, with both LNG and the degraded fraction. ß-hCG hormone has been implicated in the viability of trophoblastic cells during the first trimester of pregnancy; therefore, degraded fractions and waterborne LNG may affect reproduction in some aquatic species and humans with low level of exposure.

Supported Planar Mammalian Membranes as Models of in Vivo Cell Surface Architectures.

Emerging technologies use cell plasma membrane vesicles or "blebs" as an intermediate to form molecularly complete, planar cell surface mimetics that are compatible with a variety of characterization tools and microscopy methods. This approach enables direct incorporation of membrane proteins into supported lipid bilayers without using detergents and reconstitution and preserves native lipids and membrane species. Such a system can be advantageous as in vitro models of in vivo cell surfaces for study of the roles of membrane proteins as drug targets in drug delivery, host-pathogen interactions, tissue engineering, and many other bioanalytical and sensing applications. However, the impact of methods used to induce cell blebbing (vesiculation) on protein and membrane properties is still unknown. This study focuses on characterization of cell blebs created under various bleb-inducing conditions and the result on protein properties (orientation, mobility, activity, etc.) and lipid scrambling in this platform. The orientation of proteins in the cell blebs and planar bilayers is revealed using a protease cleavage assay. Lipid scrambling in both cell blebs and planar bilayers is indicated through an annexin V binding assay. To quantify protein confinement, immobility, etc., incorporation of GPI-linked yellow fluorescent protein (GPI-YFP) was used in conjunction with single-molecule tracking (SMT) microscopy. Finally, to investigate the impact of the bleb induction method on protein activity and expression level, cell blebs expressing human aminopeptidase N (hAPN) were analyzed by an enzyme activity assay and immunoblotting. This work enriches our understanding of cell plasma membrane bleb bilayers as a biomimetic platform, reveals conditions under which specific properties are met, and represents one of the few ways to make molecularly complete supported bilayers directly from cell plasma membranes.

When are declines in condom use while using PrEP a concern? Modelling insights from a Hillbrow, South Africa case study.

INTRODUCTION: Oral pre-exposure prophylaxis (PrEP) is a promising new prevention approach for those most at risk of HIV infection. However, there are concerns that behavioural disinhibition, specifically reductions in condom use, might limit PrEP's protective effect. This study uses the case of female sex workers (FSWs) in Johannesburg, South Africa, to assess whether decreased levels of condom use following the introduction of PrEP may limit HIV risk reduction. METHOD: We developed a static model of HIV risk and compared HIV-risk estimates before and after the introduction of PrEP to determine the maximum tolerated reductions in condom use with regular partners and clients for HIV risk not to change. The model incorporated the effects of increased STI exposure owing to decreased condom use. Noting that condom use with regular partners is generally low, we also estimated the change in condom use tolerated with clients only, to still achieve 50 and 90% risk reduction on PrEP. The model was parameterized using data from Hillbrow, Johannesburg. Sensitivity analyses were performed to ascertain the robustness of our results. RESULTS: Reductions in condom use could be tolerated by FSWs with lower baseline condom use (65%). For scenarios where 75% PrEP effectiveness is attained, 50% HIV-risk reduction on PrEP would be possible even with 100% reduction in condom use from consistent condom use as high as 70% with clients. Increased exposure to STIs through reductions in condom use had limited effect on the reductions in condom use tolerated for HIV risk not to increase on PrEP. CONCLUSIONS: PrEP is likely to be of benefit in reducing HIV risk, even if reductions in condom use do occur. Efforts to promote consistent condom use will be critical for FSWs with high initial levels of condom use, but with challenges in adhering to PrEP.

High dynamic range microscope infrared imaging of silicon nanophotonic devices.

A noninvasive diagnostic technique based on wavelength-resolved and magnified infrared images of weakly scattered light from a silicon photonic device may be useful to infer component characteristics, such as waveguide-resonator coupling, loss, quality factor, etc., at multiple locations, without the constraint of input/output couplers. Here, we demonstrate the benefit of high dynamic range microscope imaging for a silicon coupled microresonator device.