Assuring Bangladesh's future: non-communicable disease risk factors among the adolescents and the existing policy responses.

BACKGROUND: The aim of this study is to assess the current status of non-communicable disease (NCD) risk factors amongst adolescents in Bangladesh. We also critically reviewed the existing policy responses to NCD risk among adolescents in Bangladesh. METHODS: This study used a mixed method approach. To quantify the NCD risk burden, we used data from the Global School-based Student Health Survey conducted in Bangladesh. To understand policy response, we reviewed NCD-related policy documents introduced by the Government of Bangladesh between 1971 and 2018 using the WHO recommended NCD Action Plan 2013-2020as study framework. Information from the policy documents was extracted using a matrix, mapping each document against the six objectives of the WHO 2013-2020 Action Plan. RESULTS: Almost all adolescents in Bangladesh had at least one NCD risk factor, and there was a high prevalence of concurrent multiple NCD risk factors; 14% had one NCD risk factor while 22% had two, 29% had three, 34% had four or more NCD risk factors. Out of 38 policy documents, eight (21.1%) were related to research and/or surveys, eight (21.1%) were on established policies, and eleven (29%) were on legislation acts. Three policy documents (7.9%) were related to NCD guidelines and eight (21.1%) were strategic planning which were introduced by the government and non-government agencies/institutes in Bangladesh. CONCLUSIONS: The findings emphasize the needs for strengthening NCD risk factors surveillance and introducing appropriate intervention strategies targeted to adolescents. Despite the Government of Bangladesh introducing several NCD-related policies and programs, the government also needs more focus on clear planning, implementation and monitoring and evaluation approaches to preventing NCD risk factors among the adolescents in Bangladesh.

Quantifying Graphene Oxide Reduction Using Spectroscopic Techniques: A Chemometric Analysis.

The surface chemistry of graphene oxide (GO) can be modified by the chemical reduction of oxygen-containing groups using L-ascorbic acid (L-AA). Being able to "tune" the surface hydrophobicity of GO in a controlled manner, with a well-defined level of reduction, provides a valuable tool for understanding and controlling interactions with hydrophobic surfaces. Numerous analytical and chemical methods have been used to determine the extent of reduction in chemically reduced graphene oxide (CRGO) samples. However, many of these methods are limited by their laborious nature, cost, or lack of sensitivity in resolving oxygen content in samples that have only been reduced for short periods of time, making them inappropriate for rapid use with multiple samples. Here, we have used ultraviolet (UV), Raman, and attenuated total reflection infrared (ATR-IR) spectroscopy to monitor the chemical reduction of GO. These three techniques are simple, rapid, nondestructive, accurate, and widely available. The data set from each technique has been correlated and modeled against a reference data set (carbon to oxygen ratio obtained from elemental analysis) using partial least squares regression (PSLR). Using this approach, the chemical reduction of GO was quantified from UV (r2 = 0.983, RMSECV = 0.049), Raman (r2 = 0.961, RMSECV = 0.073) and ATR-IR (r2 = 0.993, RMSECV = 0.032) data. ATR-IR enabled identification of the different oxygen-containing groups on GO, and coupled with chemometric modeling, provides an excellent approach for the routine quantitative analysis of the chemical reduction of GO.

Phylogenetic relatedness of circulating HIV-1C variants in Mochudi, Botswana.

BACKGROUND: Determining patterns of HIV transmission is increasingly important for the most efficient use of modern prevention interventions. HIV phylogeny can provide a better understanding of the mechanisms underlying HIV transmission networks in communities. METHODS: To reconstruct the structure and dynamics of a local HIV/AIDS epidemic, the phylogenetic relatedness of HIV-1 subtype C env sequences obtained from 785 HIV-infected community residents in the northeastern sector of Mochudi, Botswana, during 2010-2013 was estimated. The genotyping coverage was estimated at 44%. Clusters were defined based on relatedness of HIV-1C env sequences and bootstrap support of splits. RESULTS: The overall proportion of clustered HIV-1C env sequences was 19.1% (95% CI 17.5% to 20.8%). The proportion of clustered sequences from Mochudi was significantly higher than the proportion of non-Mochudi sequences that clustered, 27.0% vs. 14.7% (p = 5.8E-12; Fisher exact test). The majority of clustered Mochudi sequences (90.1%; 95% CI 85.1% to 93.6%) were found in the Mochudi-unique clusters. None of the sequences from Mochudi clustered with any of the 1,244 non-Botswana HIV-1C sequences. At least 83 distinct HIV-1C variants, or chains of HIV transmission, in Mochudi were enumerated, and their sequence signatures were reconstructed. Seven of 20 genotyped seroconverters were found in 7 distinct clusters. CONCLUSIONS: The study provides essential characteristics of the HIV transmission network in a community in Botswana, suggests the importance of high sampling coverage, and highlights the need for broad HIV genotyping to determine the spread of community-unique and community-mixed viral variants circulating in local epidemics. The proposed methodology of cluster analysis enumerates circulating HIV variants and can work well for surveillance of HIV transmission networks. HIV genotyping at the community level can help to optimize and balance HIV prevention strategies in trials and combined intervention packages.

Electro-optical resonance modulation of vertical-cavity surface-emitting lasers.

Optical and electrical investigations of vertical-cavity surface-emitting lasers (VCSEL) with a monolithically integrated electro-optical modulator (EOM) allow for a detailed physical understanding of this complex compound cavity laser system. The EOM VCSEL light output is investigated to identify optimal working points. An electro-optic resonance feature triggered by the quantum confined Stark effect is used to modulate individual VCSEL modes by more than 20 dB with an extremely small EOM voltage change of less than 100 mV. Spectral mode analysis reveals modulation of higher order modes and very low wavelength chirp of < 0.5 nm. Dynamic experiments and simulation predict an intrinsic bandwidth of the EOM VCSEL exceeding 50 GHz.