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A phase-matching free pulse retrieval technique based on plasma-induced defocusing in a rare gas is presented. Based on a pump-probe setup, this technique uses a moderately intense pump laser pulse for ionizing the medium, creating in turn an ultrafast defocusing lens. While a coronagraph blocks out the probe pulse in absence of ionization, the plasma lens leads to increase the probe beam size in the far field. By measuring the spectrum of the probe propagating around the coronagraph as a function of the pump-probe delay π, a bi-dimensional trace (ω,π) is obtained. This enables to fully characterize the temporal and spectral characteristics of the probe pulse through a method that is free of phase matching constraints. Demonstrated both in the near-infrared (800 nm) and in the ultraviolet (266 nm), the present technique is potentially suited for characterizing pulses in the whole transparency region of the used gas, i.e., from the deep-ultraviolet to the far-infrared.

We demonstrate the generation of a persistent planar molecular alignment by subjecting a relatively warm gas sample to a resonant femtosecond laser pulse. By optically probing I_{2} molecules in their vibronic ground states, we observe a persistent delocalization of their axes near the plane orthogonal to the field direction. This phenomenon is attributed to the one-photon resonant excitation, primarily removing molecules from the thermal ground-state distribution that are initially aligned along the field, i.e., those with small projection of their rotational angular momentum along the field.

Background: Global malaria cases rose by 14 million, and deaths by 69,000, in 2020. In India, a 46% decline has been reported between 2020 and 2019. In 2017, the Malaria Elimination Demonstration Project conducted a needs-assessment of the Accredited Social Health Activists (ASHAs) of Mandla district. This survey revealed the inadequate level of knowledge in malaria diagnosis and treatment. Subsequently, a training programme was launched for enhancing malaria-related knowledge of ASHAs. The present study was conducted in 2021 to evaluate the impact of training on malaria-related knowledge and practices of ASHAs in Mandla. This assessment was also done in two adjoining districts: Balaghat and Dindori., Methods: A cross-sectional survey using a structured questionnaire was administered to ASHAs to measure their knowledge and practices related to malaria etiology, prevention, diagnosis, and treatment. A comparison of information collected from these three districts was performed using simple descriptive statistics, comparison of means and multivariate logistic regression analysis., Results: Significant improvement was noted amongst ASHAs of district Mandla between 2017 (baseline) and 2021 (endline) in knowledge related to malaria transmission, preventive measures, adherence to the national drug policy, diagnosis using rapid diagnostic tests, and identification of age group-specific, colour-coded artemisinin combination therapy blister packs (p < 0.05). The multivariate logistic regression analysis revealed that odds of Mandla baseline was 0.39, 0.48, 0.34, and 0.07 times lower for malaria-related knowledge on disease etiology, prevention, diagnosis, and treatment, respectively (p < 0.001). Further, participants in districts Balaghat and Dindori showed significantly lower odds for knowledge (p < 0.001) and treatment practices (p < 0.01) compared to Mandla endline. Education, attended training, having a malaria learner's guide, and minimum 10 years' work experience were potential predictors for good treatment practices., Conclusion: The findings of the study unequivocally establishes significant improvement in overall malaria-related knowledge and practices of ASHAs in Mandla as a result of periodic training and capacity building efforts. The study suggests that learnings from Mandla district could be helpful in improving level of knowledge and practices among frontline health workers., (© 2023. The Author(s).)

Background: Compared to 2017, India achieved a significant reduction in malaria cases in 2020. Madhya Pradesh (MP) is a tribal dominated state of India with history of high malaria burden in some districts. District Mandla of MP state showed a considerable decline in malaria cases between 2000 and 2013, except in 2007. Subsequently, a resurgence of malaria cases was observed during 2014 and 2015. The Malaria Elimination Demonstration Project (MEDP) was launched in 2017 in Mandla with the goal to achieve zero indigenous malaria cases. This project used: (1) active surveillance and case management using T4 (Track fever, Test fever, Treat patient, and Track patient); (2) vector control using indoor residual sprays and long-lasting insecticidal nets; (3) information education communication and behaviour change communication; and (4) regular monitoring and evaluation with an emphasis on operational and management accountability. This study has investigated malaria prevalence trends from 2008 to 2020, and has predicted trends for the next 5 years for Mandla and its bordering districts., Methods: The malaria prevalence data of the district Mandla for the period of January 2008 to August 2017 was obtained from District Malaria Office (DMO) Mandla and data for the period of September 2017 to December 2020 was taken from MEDP data repository. Further, the malaria prevalence data for the period of January 2008 to December 2020 was collected from DMOs of the neighbouring districts of Mandla. A univariate time series and forecast analysis was performed using seasonal autoregressive integrated moving average model., Findings: Malaria prevalence in Mandla showed a sharp decline [- 87% (95% CI - 90%, - 84%)] from 2017 to 2020. The malaria forecast for Mandla predicts zero cases in the next 5 years (2021-2025), provided current interventions are sustained. By contrast, the model has forecasted a risk of resurgence of malaria in other districts in MP (Balaghat, Dindori, Jabalpur, Seoni, and Kawardha) that were not the part of MEDP., Conclusion: The interventions deployed as part of MEDP have resulted in a sustainable zero indigenous malaria cases in Mandla. Use of similar strategies in neighbouring and other malaria-endemic districts in India could achieve similar results. However, without adding extra cost to the existing intervention, sincere efforts are needed to sustain these interventions and their impact using accountability framework, data transparency, and programme ownership from state to district level., (© 2023. The Author(s).)