Circular dichroism simulated spectra of chiral gold nanoclusters: A dipole approximation

Circular dichroism (CD) spectra of chiral bare and thiol-passivated gold nanoclusters have been calculated within the dipole approximation. The calculated CD spectra show features that allow us to distinguish between clusters with different indexes of chirality. The main factor responsible of the differences in the CD lineshapes is the distribution of interatomic distances that characterize the chiral cluster geometry. These results provide theoretical support for the quantification of chirality and its measurement, using the CD lineshapes of chiral metal nanoclusters.Comment: 3 pages + 4 figure

Evaluación de metodología AASHTO y SHELL para el diseño de pavimento de la vía “Caracolí” que conecta a “la carretera del amor” en Villavicencio - Meta

Hoy día el mundo cuenta con diferentes métodos para el diseño de pavimentos flexibles que se diferencian entre sí, por las ecuaciones y nivel de información que requieren. Si bien es cierto que en Colombia se utiliza el método AASHTO 93, es válido cuestionarse respecto de la conveniencia de explorar y analizar otros métodos que pudiesen ser aplicables en el país. Teniendo en cuenta lo anterior, en este proyecto se estudiaron y compararon los métodos de diseño semiempírico (AASHTO 93) y mecanicista-racional (SHELL 78). Para ello se realizó en primera instancia una comparación teórica de los métodos seleccionados en cuanto al enfoque y al nivel de información requerido por cada método. Posteriormente se realizó una comparación de resultados obtenidos por los distintos métodos, en una serie de escenarios definidos para la vía “Caracolí”, en el municipio de Villavicencio en el Meta, según variables de tránsito, subrasante y clima. Al igual que en términos de espesores de capa y costo de materiales. Los resultados indicaron que el método más conservador, considerando los espesores de las capas de una estructura de pavimento flexible y los costos que ello implica, es el método AASHTO 93. Sin embargo, el método que considera una mayor cantidad de información, es el de SHELL 78, porque que ha logrado determinar las combinaciones de espesores de las diferentes capas del pavimento que garantizan el cumplimiento de los valores de deformación por tracción en las capas asfálticas (εt) y la deformación vertical por compresión en la subrasante (εz) durante el periodo de diseño, este método supone la estructura del pavimento como un sistema multicapa linealmente elástico, bajo la gestión de las cargas de tránsito, en el cual los materiales se hallan por su módulo de elasticidad. La principal recomendación es complementar los resultados obtenidos con programas más actualizados que incorporen el análisis de los datos según un método empírico-mecanicista.Nowadays, the world has different methods for the design of flexible pavements that differ from each other, due to the equations and level of information they require. Although it is true that the AASHTO 93 method is used in Colombia, it is valid to question the advisability of exploring and analyzing other methods that could be applicable in the country. Bearing in mind the above, in this project the semi-empirical (AASHTO 93) and mechanistic-rational (SHELL 78) design methods were studied and compared. Taking this in place, a theoretical comparison of the selected methods was carried out in the first instance in terms of the approach and the level of information required by each method. Subsequently, a comparison was made of the results obtained by the different methods, in a series of scenarios defined for the "Caracolí" road, in the small townof Villavicencio at Meta, according to variables of traffic, subgrade and weather as well as in terms of layer thicknesses and cost of materials. Furthermore, the results indicated that the most conservative method, considering the thickness of the layers of a flexible pavement structure and the costs that this implies, is the AASHTO 93 method. Nonetheless, the method that considers a greater amount of information is by SHELL 78 because it has managed to determine the combinations of thicknesses of the different layers of the pavement that tensile strain in the asphalt layers (εt) and vertical compression strain in the subgrade (εz) values during the design period, this method assumes the pavement structure as a linearly elastic multilayer system, under the management of the traffic loads, in which materials are found by their modulus of elasticity. The main recommendation is to complement the results obtained with more updated programs that incorporate a complete data analysis according to an empirical-mechanistic method.http://www.ustavillavicencio.edu.co/home/index.php/unidades/extension-y-proyeccion/investigacionPregrad

Effect of lipid-based nutrient supplement - medium quantity on reduction of stunting in children 6-23 Months of age in Sindh, Pakistan: A cluster randomized controlled trial (OR25-06-19)

Objectives: We evaluated the effectiveness of a locally produced lipid-based nutrient supplement - medium-quantity (LNS-MQ) known as Wawamum to prevent stunting in children 6–23 months of age in Thatta and Sujawal districts of Sindh province, Pakistan. Methods: A cluster randomized controlled trial was conducted and a total of 870 children between 6–18 months old were enrolled. Children in the intervention group received 50 grams/day of Wawamum for 6 months, while children in the control group received standard government health services, not including Wawamum. The primary outcome was stunting risk reduction among children 6–23 months of age. Results: Children who received Wawamum were found to have a significantly reduced risk of stunting (RR = 0.91, 95% CI; 0.88– 0.94, P \u3c 0.001) and wasting (RR = 0.78, 95% CI; 0.67–0.92, p0.004) as compared to children who received the standard government health services. A non-significant impact was observed on underweight (RR = 0.94, 95% CI; 0.85–1.04, p-0.241) in the intervention group compared to the control group. Statistically significant reduction in anaemia in the intervention group was also found as compared to the control group (RR = 0.97, 95% CI; 0.94–0.99, p-0.008). The reduction in risk of severe anaemia was even more evident (RR = 0.45, 95% CI; 0.28–0.99, p-0.002) in the intervention group than in the control group. The mean compliance of Wawamum was 60.3% among children. Conclusions: The study confirmed the plausibility of achieving nutrition gains in the short-term with a locally produced LNS-MQ, known as Wawamum, through the primary health care system. The risk of stunting and wasting was reduced by 9% and 22%, respectively. The statistically significant reduction in risk of stunting, wasting and anaemia among children 6–23 months of age showed that an immediate improvement in these nutrition indicators is indeed possible. This approach can be scaled up in similar settings to achieve positive outcomes for nutrition and health. Funding Sources: World Health Organization

Life in the surf-zone: Variations of faunal assemblage structure in temperate sandy beaches of the Southwestern Atlantic coast

This study explores the changes of biological descriptors -richness, diversity and abundance-of faunal surf-zone assemblage along a temperate coastal fringe. Three mesotidal sandy beaches with different morphodynamic states, adjacent to an estuarine zone, were seasonally sampled during a year. Zooplankton, zoobenthos and fish samples were taken in the surf-zone and a set of potential explanatory environmental variables were measured and/or quantified. Generalized linear models (GLM) were employed to compare environmental and biological variables between beaches and seasons. Beaches varied from tide-dominated flat to tide-modified reflective to intermediate. The assemblage included 108 taxa, of which few were numerically dominant. Richness of each biological group was similar along the shore and higher values of α-diversity were associated with minimum values of total abundance. β-diversity was mainly a consequence of species turnover, mostly due to changes in zoobenthic and zooplanktonic taxa. Results of GLM test showed that seasons and beaches have an interdependent effect on the abundance of the surf-zone assemblage. All biological groups showed marked seasonal variability in its occurrence, possibly associated with environmental variables, such as temperature and photosynthetic pigment concentrations. Zooplankton and fish groups reached maximum abundance, during autumn and spring respectively, in tide-modified beaches where the surf-zone was well developed and waves reached higher heights. Zoobenthic abundance peaked in beaches with narrower surf-zone and lower wave energy, during autumn, winter and spring, which could be advantageous for those taxa that escape from predators by burying or for species that actively swim near the seafloor. The copepod Acartia tonsa, the clupeidae fish Ramnogaster arcuata and the mysids Arthromysis magellanica and Neomysis americana all typical species of the neighboring estuary, were the main responsibles for these distribution patterns. The connection of the surf-zone with the adjacent estuarine area is also evident by its role in enriching the dissolved organic matter of surf-waters.Fil: Fiori, Sandra Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Martinez, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Carcedo, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Blasina, Gabriela Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Garzon Cardona, John Edison. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Moyano, Jessica Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Menendez, Maria Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

Effectiveness of specialized nutritious foods and social and behavior change communication interventions to prevent stunting among children in Badakhshan, Afghanistan: Protocol for a quasi-experimental study

Stunting predominantly occurs during the first 1000 days of life and continues to the age of five years. We will aim to assess the effectiveness of specialized nutritious foods (SNF)and social and behavior change communication (SBCC) strategies during the first 1000 days of life to prevent stunting among children in two rural districts of Badakhshan, Afghanistan. This will be a quasi-experimental pre-post study with the control group utilizing qualitative and quantitative methods. Before launching the program, formative research will be conducted on the acceptability, appropriate use and SBCC strategies needed to support the introduction of intervention package. Repeated cross-sectional baseline and endline surveys will be conducted in both the intervention and the control districts. After the formative research and baseline household survey, an intervention focusing on the provision of SNF, targeting pregnant and lactating women and children 6-23 months, and SBCC strategies will be implemented for at least 12 months. The primary outcome will be a reduction in the prevalence of stunting among children under two years in the intervention group compared to the control group. We will aim to compare the intervention and control group between the pre- and post-intervention assessments to isolate the effect of the intervention by difference-in-differences estimates. The program monitoring and evaluation component will examine the quality of implementation, acceptability of intervention, identification of potential barriers and to learn how to enhance the program\u27s effectiveness through ongoing operational improvements. The results will be beneficial to design interventions to prevent stunting within Afghanistan and other low-middle-income countries

Effect of lipid-based nutrient supplement-Medium quantity on reduction of stunting in children 6-23 months of age in Sindh, Pakistan: A cluster randomized controlled trial

Background: Chronic childhood malnutrition, or stunting, remains a persistent barrier to achieve optimal cognitive development, child growth and ability to reach full potential. Almost half of children under-five years of age are stunted in the province of Sindh, Pakistan.Objective: The primary objective of this study was to test the hypothesis that the provision of lipid-based nutrient supplement-medium-quantity (LNS-MQ) known as Wawamum will result in a 10% reduction in risk of being stunted at the age of 24 months in the intervention group compared with the control group.Design: A cluster randomized controlled trial was conducted in Thatta and Sujawal districts of Sindh province, Pakistan. A total of 870 (419 in intervention; 451 in control) children between 6-18 months old were enrolled in the study. The unit of randomization was union council and considered as a cluster. A total of 12 clusters, 6 in each study group were randomly assigned to intervention and control group. All children received standard government health services, while children in the intervention group also received 50 grams/day of Wawamum.Results: Children who received Wawamum were found to have a significantly reduced risk of stunting (RR = 0.91, 95% CI; 0.88-0.94, p\u3c0.001) and wasting (RR = 0.78, 95% CI; 0.67-0.92, p = 0.004) as compared to children who received the standard government health services. There was no evidence of a reduction in the risk of underweight (RR = 0.94, 95% CI; 0.85-1.04, p = 0.235) in the intervention group compared to the control group. Statistically significant reduction in anaemia in the intervention group was also found as compared to the control group (RR = 0.97, 95% CI; 0.94-0.99, p = 0.042). The subgroup analysis by age, showed intervention effect is significant in reduction of risk of stunting in younger children of aged 6-12 month (RR = 0.83, 95% CI; 0.81-0.86, p = \u3c0.001) and their older peers aged 13-18 month- (RR = 0.90, 95% CI; 0.83-0.97, p = 0.008). The mean compliance of Wawamum was 60% among children.Conclusions: The study confirmed that the provision of Wawamum to children 6-23 months of age is effective in reducing the risk of stunting, wasting and anaemia. This approach should be scaled up among the most food insecure areas/households with a high prevalence of stunting to achieve positive outcomes for nutrition and health. This study was registered at clinicaltrials.gov as NCT02422953. Clinical Trial Registration Number: NCT02422953

Sleep disorders and hyperarousal among patients with endometriosis: A case-control survey study

Background: Endometriosis has been associated with sleep disorders, and hyperarousal appears to be involved in their pathogenesis; however, the presence of hyperarousal in the endometriosis population was never investigated. Methods: We conducted a case-control survey study by sending a questionnaire to all endometriosis patients followed up at our Centers. Controls were recruited among the general population. The questionnaire included demographic information, symptoms and history of endometriosis, the Hyperarousal Scale (H-Scale), the Pittsburgh Sleep Quality Index (PSQI), and the Insomnia Severity Index (ISI). Results: A total of 847 women completed the questionnaires: 430 (50.8 %) had endometriosis, and 417 (49.2 %) were controls. Endometriosis was associated with higher H-scale score (OR 2.9, 95 % CI 2.4-3.8, p = 0.000), higher PSQI score (OR 4.3, 95 % CI 3.2-5.7, p = 0.000), and higher ISI score (OR 4.6, 95 % CI 3.5-6.1, p = 0.000) in multivariable ordinal logistic regressions analysis. With path analysis, hyperarousal (H-Scale) reported a partial mediating role in the association between endometriosis and sleep disorders. The mediation effect represented 22.3-27.8 % of the entire association between endometriosis and sleep disturbances. Conclusion: Endometriosis patients complaining sleep disorders may benefit by investigating the presence of hyperarousal given cognitive behavioral therapy was reported effective in improving hyperarousal and associated sleep disorders

Effectiveness of unconditional cash transfers combined with lipid-based nutrient supplement and/or behavior change communication to prevent stunting among children in Pakistan: A cluster randomized controlled trial

Background: In Pakistan, the prevalence of stunting among children under-five years has remained above WHO critical thresholds (≥30%) over the last two decades.Objective: We hypothesized that an unconditional cash transfer (UCT) combined with lipid-based nutrient supplement (LNS) and/or social and behavior change communication (SBCC) will prevent stunting among children 6-23 months of age.Design: This was a four-arm, community-based cluster randomized controlled trial conducted in the district of Rahim Yar Khan, Pakistan. A total of 1729 children (UCT n = 434); (UCT+SBCC n = 433); (UCT+LNS n = 430) and (UCT+LNS+SBCC n = 432) were enrolled at 6 months of age and measured monthly for 18 months until the age of 24 months.Results: At 24 months of age, children who received UCT+LNS (rate ratio [RR], 0.85 [95% CI 0.74, 0.97]; P = 0.015); and UCT+LNS+SBCC (RR, 0.86 [95% CI 0.77, 0.96]; P = 0.007) had significantly lower risk of being stunted as compared to the UCT arm. No significant difference was noted among children who received UCT+SBCC (RR, 1.03 [95% CI 0.91, 1.16]; P = 0.675) in the risk of being stunted as compared to the UCT arm. The pooled prevalence of stunting among children 6-23 months was 41.7%, 44.8%, 38.5% and 39.3% in UCT, UCT+SBCC, UCT+LNS and UCT+LNS+SBCC, respectively. In pairwise comparisons, a significant impact on stunting among children in UCT+LNS (P = 0.029) and UCT+LNS+SBCC (P = \u3c0.001) was noted as compared to UCT arm.Conclusions: UCT combined with LNS and UCT+LNS+SBCC were effective in reducing the prevalence of stunting among children aged 6-23 months in marginalized populations. UCT+SBCC was not effective in reducing the child stunting prevalence.Clinical trial registration number: ClinicalTrials.gov NCT03299218

Specialized nutritious food combined with cash transfers and social and behavior change communication to prevent stunting among children aged 6 to 23 months in Pakistan: Protocol for a cluster randomized controlled trial

Background: In Pakistan, the prevalence of stunting in children younger than 5 years has remained above global critical levels over the past two decades, with the stunting rate being 40.2% in 2018. Children living in rural areas and in the poorest households suffer the most from stunting across the country-43.2% in rural areas and 51.4% in the lowest wealth quintile. As a continuing public health concern, it is essential that stunting prevention is a national priority in order to ensure human capital development, especially among the poorest households.Objective: The primary objective of this study is to determine the effect of a medium quantity of a lipid-based nutrient supplement (LNS) combined with unconditional cash transfers and social and behavior change communication (SBCC) on reduction of stunting in children aged 6 to 23 months.Methods: A 5-arm cluster randomized controlled trial will be conducted in the district of Rahim Yar Khan in Punjab, Pakistan. The intervention packages will be (1) cash only, (2) cash with LNS, (3) cash with SBCC, and (4) cash with SBCC and LNS. The control arm will receive routine standard of care. We will enroll children at 6 months of age and follow up on a monthly basis up to 24 months of age. A total of 2000 children, 400 in each arm, will be enrolled to detect a 20% reduction in the prevalence of stunting among children aged 24 months. Length, weight, food intake, compliance to interventions, morbidities, and other relevant data will be collected at enrollment and on a monthly basis over the period of 18 months. The process evaluation will assess acceptability of the interventions and potential barriers to implementation through focus group discussions and in-depth interviews with the target population and relevant stakeholders. Furthermore, a cost analysis will be conducted to assess the cost-effectiveness of each intervention package.Results: The study protocol was approved by the Ethics Review Committee of Aga Khan University in Pakistan on January 4, 2017. Data collection began in May 2017 and was completed in July 2019. Data analyses are yet to be completed. This study will explore the effectiveness of intervention packages comprised of cash transfers from Benazir Income Support Programme with or without additional LNS and SBCC in preventing childhood stunting. We expect the results to be published in peer-reviewed journals by autumn of 2020.Conclusions: The findings of this trial will provide robust evidence as to which intervention packages can have significant effects on linear growth of children and design effective intervention packages to prevent stunting in children aged 6 to 23 months

Knockout of the dhfr-ts Gene in Trypanosoma cruzi Generates Attenuated Parasites Able to Confer Protection against a Virulent Challenge

Chagas disease is the clinical manifestation of the infection produced by the flagellate parasite Trypanosoma cruzi and currently there is no vaccine to prevent this disease. Therefore, different approaches or alternatives are urgently needed. Vaccination with live attenuated parasites has been used effectively in mice to reduce parasitemia and histological damage. However, the use of live parasites as inmunogens is controversial due to the risk of reversion to a virulent phenotype. In this work we genetically manipulated a naturally attenuated strain of T. cruzi in order to produce parasites with impaired replication and infectivity, using the mutation as a safety device against reversion to virulence. We show that genetically modified parasites display a lower proliferation rate in vitro and induced almost undetectable levels of T. cruzi specific CD8+ T cells when injected in mice. Furthermore, the immune response induced by these live mutant parasites confers protection against a subsequent virulent infection even a year after the original immunization