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This paper presents the successful synthesis of AgInS2nanocrystals (NCs) double-shelled with GaSxand ZnS for emitting bright and narrow excitonic luminescence from AgInS2core NCs. Additionally, the AgInS2/GaSx/ZnS NCs with a core/double-shell structure have demonstrated high chemical and photochemical stability. The AgInS2/GaSx/ZnS NCs were prepared via three steps: (i) synthesis of AgInS2core NCs by solvothermal method at 200 °C for 30 min, (ii) shelling GaSxon AgInS2core NCs at 280 °C for 60 min to produce the AgInS2/GaSxcore/shell structure, and (iii) the outermost ZnS shelling at 140 °C for 10 min. The synthesized NCs were characterized in detail by using appropriate techniques such as x-ray diffraction, transmission electron microscopy, and optical spectroscopies. The luminescence evolution of the synthesized NCs is as follows: from the broad spectrum (peaking at 756 nm) of the AgInS2core NCs to become the narrow excitonic emission (at 575 nm) prominent beside the broad one after shelling with GaSx, then only the bright excitonic luminescence (at 575 nm) without broad emission after double-shelling with GaSx/ZnS. The double-shell has made the AgInS2/GaSx/ZnS NCs not only remarkably enhance their luminescence quantum yield (QY) up to â¼60% but also maintain the narrow excitonic emission stably for a long-term storage over 12 months. The outermost ZnS shell is believed to play a key role in enhancing QY and protecting AgInS2and AgInS2/GaSxfrom certain damage.
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BACKGROUND: Poor early-life nutrition is a major barrier to good health and cognitive development, and is a global health priority. Alive & Thrive (A&T) was a multi-pronged initiative to improve infant and young child feeding behaviors. It aimed to achieve at-scale child health and nutrition improvements via a comprehensive approach that included nutrition counseling by health workers, policy change, social mobilization and mass media activities. This study evaluated the sustainability of activities introduced during A&T implementation (2009-2014) in Bangladesh and Vietnam. METHODS: This was a mixed methods study that used a quasi-experimental design. Quantitative data (surveys with 668 health workers, and 269 service observations) were collected in 2017; and analysis compared outcomes (primarily dose and fidelity of activities, and capacity) in former A&T intervention areas versus areas that did not receive the full A&T intervention. Additionally, we conducted interviews and focus groups with 218 stakeholders to explore their impressions about the determinants of sustainability, based on a multi-level conceptual framework. RESULTS: After program conclusion, stakeholders perceive declines in mass media campaigns, policy and advocacy activities, and social mobilization activities - but counseling activities were institutionalized and continued in both countries. Quantitative data show a persisting modest intervention effect: health workers in intervention areas had significantly higher child feeding knowledge, and in Bangladesh greater self-efficacy and job satisfaction, compared to their counterparts who did not receive the full package of A&T activities. While elements of the program were integrated into routine services, stakeholders noted dilution of the program focus due to competing priorities. Qualitative data suggest that some elements, such as training, monitoring, and evaluation, which were seen as essential to A&T's success, have declined in frequency, quality, coverage, or were eliminated altogether. CONCLUSIONS: The inclusion of multiple activities in A&T and efforts to integrate the program into existing institutions were seen as crucial to its success but also made it difficult to sustain, particularly given unstable financial support and human resource constraints. Future complex programs should carefully plan for institutionalization in advance of the program by cultivating champions across the health system, and designing unique and complementary roles for all stakeholders including donors.
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Serviços de Saúde da Criança , Promoção da Saúde/organização & administração , Bangladesh , Criança , Saúde da Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Aconselhamento , Feminino , Pessoal de Saúde , Promoção da Saúde/métodos , Humanos , Lactente , Masculino , Meios de Comunicação de Massa , Estado Nutricional , Avaliação de Programas e Projetos de Saúde/métodos , VietnãRESUMO
Objective: Human respiratory syncytial virus (RSV) is a primary cause of paediatric severe acute respiratory infection (SARI) worldwide, especially in developing countries. We investigated the genetic characteristics of RSV in northern Viet Nam to determine the prevalence and distribution of subtypes as well as the diversity and transmission patterns of genotypes. Methods: In two facilities, from January 2017 to December 2020, 1563 clinical specimens were collected from paediatric patients hospitalized with SARI and tested for RSV. Selected positive samples underwent sequencing analysis targeting the second hypervariable region of the G gene using next-generation sequencing. Results: The RSV positivity rate was 28.02% (438/1563 samples), and prevalence was highest in children aged < 1 year (43.84%; 192/438). Subtype RSV-A accounted for 53.42% (234/438) of cases, RSV-B for 45.89% (201/438), and there was coinfection in 0.68% (3/438). Both subtypes cocirculated and peaked during August-September in each year of the study. Phylogenetic analysis showed that RSV-A samples belonged to the ON1 genotype, which has three subgenotypes: ON1.1, ON1.2 and ON1.3. However, we did not find the 72-nucleotide duplication in the second hypervariable region of the G gene, a characteristic of genotype ON1, in any RSV-A samples. RSV-B samples belonged to genotype BA9. Discussion: Our results provide additional molecular characterization of RSV infections in Viet Nam. Specially, our study is the first to report the absence of the 72-nucleotide duplication in the G gene of RSV-A genotype ON1 in Viet Nam, which may help in understanding the genetic evolution of RSV and be useful for vaccine development in the future.
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Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Humanos , Lactente , Vírus Sincicial Respiratório Humano/genética , Filogenia , Vietnã/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Genótipo , NucleotídeosRESUMO
Policy research can reveal gaps and opportunities to enhance policy impact and implementation. In this study, we use a theoretically informed qualitative approach to investigate the implementation of two policies to promote breastfeeding in Vietnam. We conducted semi-structured interviews with national and local policy stakeholders (n = 26) in 2017. Interviews were audio-recorded, transcribed verbatim and then translated to English by certified translators. Transcript data were analysed using an integrated conceptual framework of policy implementation. Respondents identified several positive outcomes resulting from implementation of an extended maternity leave policy (Labour Code No. 10/2012/QH13) and further restrictions on marketing of breast milk substitutes (Decree No. 100/2014/ND-CP). Decree No. 100, in particular, was said to have reduced advertising of breast milk substitutes in mass media outlets and healthcare settings. Key implementation actors were national-level bureaucratic actors, local organizations and international partners. Findings reveal the importance of policy precedence and a broader set of policies to promote the rights of women and children to support implementation. Other facilitators were involvement from national-level implementing agencies and healthcare personnel and strength of government relationships and coordination with non-governmental and international organizations. Implementation challenges included insufficient funding, limited training to report violations, a cumbersome reporting process and pervasive misinformation about breast milk and breast milk substitutes. Limited reach for women employed in the informal labour sector and in rural communities was said to be a compatibility issue for the extended maternity leave policy in addition to the lack of impact on non-parental guardians and caretakers. Recommendations to improve policy implementation include designating a role for international organizations in supporting implementation, expanding maternity protections for all working women, building local-level policy knowledge to support enforcement, simplifying Decree No. 100 violation reporting processes and continuing to invest in interventions to facilitate a supportive policy environment in Vietnam.
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Substitutos do Leite , Licença Parental , Aleitamento Materno , Criança , Feminino , Humanos , Marketing , Política Nutricional , Gravidez , VietnãAssuntos
Encefalite Viral/epidemiologia , Encefalite Viral/prevenção & controle , Hospitais Pediátricos/estatística & dados numéricos , Programas de Imunização/estatística & dados numéricos , Doença Aguda , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/prevenção & controle , Humanos , Vacinas contra Encefalite Japonesa/administração & dosagem , Estações do Ano , VietnãRESUMO
Tin and its derivatives have provoked tremendous progress of high-capacity sodium-ion anode materials. However, achieving high areal and volumetric capability with maintained long-term stability in a single electrode remains challenging. Here, an elegant and versatile strategy is developed to significantly extend the lifespan and rate capability of tin sulfide nanobelt electrodes while maintaining high areal and volumetric capacities. In this strategy, in situ bundles of robust hierarchical graphene (hG) are grown uniformly on tin sulfide nanobelt networks through a rapid (5 min) carbon-plasma method with sustainable oil as the carbon source and the partially reduced Sn as the catalyst. The nucleation of graphene, CN (with size N ranging from 1 to 24), on the Sn(111) surface is systematically explored using density functional theory calculations. It is demonstrated that this chemical-bonded hG strategy is powerful in enhancing overall electrochemical performance.