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Aluminum (Al) and its alloys are popular in the aerospace industry due to their high strength-to-weight ratio, corrosion resistance, and ductility. However, these properties (extreme ductility and malleability) can compromise corrosion resistance, making them susceptible to dents and scratches. Silicon Carbide (SiC) is a promising alternative to Al and it alloys due to its higher Youngs modulus and excellent wear resistance, although it has the drawbacks of brittleness and higher density. This study investigated the structural and mechanical properties of SiC alloyed with lithium (SiC-Li) or sodium (SiC-Na) using ab initio calculations with the aim of tuning the structural and mechanical properties of SiC. Modeling was done using Burai software, which offers a friendly graphical user interface for Quantum ESPRESSO, thus facilitating the creation of input files, visualization of crystal structures and analysis of results. The results from this study showed that the addition of Li and Na lowered the density as well as the mechanical properties of SiC but still being favorably better than those of Al and its alloys, suggesting that the modeled alloys could potentially replace the traditional Al and its alloys in the aerospace industry. Further experimental studies are needed to validate these findings and to explore the possibility of simultaneous alloying of SiC with both Li and Na for enhanced performance.

Speakers of many languages have limited content available on the web in their native languages and thus, look for information on the Internet in English. Query formulations, search results selection decisions, credibility judgments on results, and other aspects of information seeking and retrieval have been found to be difficult when conducting the search in a language and culture other than the searcher’s native one. The purpose of this research is to further understand non-native English speakers’ information search behavior and content selection decisions. In the initial study phase, qualitative methods are applied to examine selection decisions about web search results. The results align with search result selection criteria from prior work and identify some web content selection criteria that non-native English language searchers employ. During the second phase of the research, an understudied population is targeted and the research questions extended in order to provide a thick, rich description. An exploratory interview is conducted to better understand the research context and information-seeking practices. Interviews are conducted to investigate general aspects around the information search process, Internet use, modes of Internet access and search result selection decisions. In-depth, in person interviews, an Internet search task and a self-reported survey are administered to investigate context, selection decisions and credibility perceptions around web content. The results outline the context of technology-mediated information seeking for middle class web searchers in the developing region and the impacts of the characteristics of this context on information seeking behavior. Findings reveal a complex context of expensive, limited Internet access leading to complex coping strategies such as deliberate interactions, device sharing, SIM card swapping, and data-intensive searching with free access. The research highlights criteria that the web searchers consider when selecting content including: author and source credentials, reputation, recommendations from others, comprehensive content, highly ranked content on the search engine and professionally presented content. The research further reveals criteria influencing a site’s credibility perceptions including: comprehensive content sources, recommendations from trusted parties, professional and appropriate designs, authoritative and respected sources, the existence of reachable entities behind the site, and site affiliations via links and references.

Hunts Point, a 690-acre peninsula in the South Bronx, New York City, is a hub in the tristate (New York, New Jersey, and Connecticut) freight transportation system. This study was carried out in response to community concerns about potential health effects of exposure to diesel exhaust particulate (DEP). We measured particulate matter < 2.5 microm in aerodynamic diameter (PM(2.5)) and elemental carbon (EC) on sidewalks and tested whether spatial variations in concentrations were related to local truck traffic density. Ten-hour integrated air samples for EC and PM(2.5) were collected for 9 days over a 3-week period in the summer of 1999 at seven geographically distinct intersections. Simultaneous traffic counts were carried out for each sampling event. Traffic was classified into three classes: passenger cars, small trucks, and large trucks (diesel vehicles). Mean diesel vehicle volumes ranged from 9.3 to 276.5 vehicles/hr across sites. Mean EC concentrations by site ranged from 2.6 microg/m(3) at the control site to 7.3 microg/m(3) along a designated truck route. Linear regression of site-specific mean EC concentration on mean large truck counts predicted an increase of 1.69 microg/m(3) EC per 100 large trucks/hr (SE = 0.37; p = 0.01; R(2) = 0.84). Average PM(2.5) concentrations by site ranged 1.6-fold (19.0-29.9 microg/m(3)) and were more weakly associated with local traffic. Variations over time for PM(2.5 )were more pronounced, ranging almost 4-fold (8.9-34.4 microg/m(3)). These results show that airborne EC concentrations, an important component of DEP, are elevated in Hunts Point and that the impact varies across the community as a function of large truck traffic.

Hunts Point, a 690-acre peninsula in the South Bronx, New York City, is a hub in the tristate (New York, New Jersey, and Connecticut) freight transportation system. This study was carried out in response to community concerns about potential health effects of exposure to diesel exhaust particulate (DEP). We measured particulate matter < 2.5 μm in aerodynamic diameter ( PM2.5) and elemental carbon (EC) on sidewalks and tested whether spatial variations in concentrations were related to local truck traffic density. Ten-hour integrated air samples for EC and PM2.5were collected for 9 days over a 3-week period in the summer of 1999 at seven geographically distinct intersections. Simultaneous traffic counts were carried out for each sampling event. Traffic was classified into three classes: passenger cars, small trucks, and large trucks (diesel vehicles). Mean diesel vehicle volumes ranged from 9.3 to 276.5 vehicles/hr across sites. Mean EC concentrations by site ranged from 2.6 μ g/ m3at the control site to 7.3 μ g/ m3along a designated truck route. Linear regression of site-specific mean EC concentration on mean large truck counts predicted an increase of 1.69 μ g/ m3EC per 100 large trucks/hr (SE = 0.37; p = 0.01; R2=0.84). Average PM2.5concentrations by site ranged 1.6-fold (19.0-29.9 μ g/ m3) and were more weakly associated with local traffic. Variations over time for PM2.5were more pronounced, ranging almost 4-fold (8.9-34.4 μ g/ m3). These results show that airborne EC concentrations, an important component of DEP, are elevated in Hunts Point and that the impact varies across the community as a function of large truck traffic.

Background: Infant growth faltering is common in developing countries. A major cause is inappropriate feeding practices and poor quality complementary foods with low energy density and deficiency in micronutrients and which may displace breast milk. The impact of micronutrient fortification of complementary foods or adding a-amylase to increase energy density on growth of infants from middle income urban populations in developing countries has been inadequately studied. Objectives: To assess current complementary feeding practices, develop and test the acceptability and effect of amylase-treated-fortified complementary blends named Chilenje Baby Mix (CBM) on growth and haemoglobin concentration of infants from a middle income community in Lusaka, Zambia. Design: Three-stage study comprising assessment of, 1) current complementary feeding practices, 2) acceptability of amylase-treated-fortified complementary food and, 3) the effect of the complementary food on growth, haemoglobin concentration and breast milk intake of 9-month old infants in a randomized controlled trial. Methods: Current complementary feeding practices were assessed by qualitative (focus group discussions, interviews and home observations) and quantitative methods. Acceptability to mothers of roasted maize-beans-groundnuts- bambaranuts porridge recipes was assessed prior to the industrial production of a- amylase-treated-fortified blends. Infants were randomized to receive a fortified blend with (CBMA) or without amylase (CBM) from 6-9 months of age. Anthropometric measurements, dietary intake and morbidity were determined monthly. Non-intervention infants were measured at 9 months of age. Breast milk intake was determined by deuterium oxide dilution method in a non-random subset of infants at 9 months. Results: Mothers had wide knowledge on optimal infant feeding, but actual practices were constrained by food cost and time availability, a-amylase enhanced porridge acceptability and caused 1000-fold reduction in porridge viscosity. The developed blend cost half as much as the average price of commercially complementary foods in the market. Mean weight gain between 6 and 9 months was 1.0 (SD 0.6) kg, 0.9 (SD 0.6) kg and 0.9 (SD 0.5) kg for infants in the CBM, CBMA and control groups, respectively (p = 0.54). Mean length at 9 months was 71.8 (SD 2.5) cm, 71.3 (SD 1.5) cm and 70.9 (SD 2.4) cm for infants in the CBM, CBMA and control groups, respectively (p = 0.06) infants in CBM had significantly greater length (p = 0.04) than infants in the control group by least square differences. Infants in both CBM and CBMA had significantly greater biceps (p = 0.02), subscapular (p < 0.001) and suprailiac skinfolds (< 0.001) and percent fat mass (p = 0.01) than infants in the control group. Infants in both CBM and CBMA had significantly greater haemoglobin concentration (p = 0.03) than infants in the control group 104 (SD 12) g/L, 103 (SD 12) g/L and 98 (SD 14) g/L for CBM, CBMA and control groups, respectively . The mean breast milk intake was 614 (SD 271) g/day, 635 (SD 193) g/day and 653 (SD 221) g/day (p = 0.87) and the mean energy intakes from breast milk and complementary foods represented 116%, 112% and 115% of the RDA for infants in CBM, CBMA and control groups, respectively. Infants in both CBM and CBMA had significantly greater intakes of calcium (p = 0.01), iron (p < 0.001), zinc (p < 0.001), vitamin A (p = 0.01), vitamin C (p < 0.001), thiamine (p = 0.03) and riboflavin (p = 0.02) than infants in the control group. Conclusion A cheap and acceptable industrially processed fortified complementary blend was developed. The porridge blend resulted in moderate improvement in infant length, but had more obvious improvement in haemoglobin concentration without adverse effect on breast milk intake. This blend may be used to improve micronutrient status and health of infants in middle income urban communities in developing countries.

Good nutrition is a prerequisite for a healthy and active life, especially for agriculture-dependent households. However, diets in most households in Tanzania lack diversity because the intake of meat, poultry, fish, and vegetables and fruits is low. This study estimates factors influencing dietary diversity of the household, children under five years, and women using primary survey data. It qualitatively assesses male dietary patterns and men's potential role in improving the nutritional status of the entire household. The findings show that the most consumed foods within the household are cereals, vegetables, oils and fats, spices, condiments and beverages. Children (d = 0.4; p<0.05) and women (d = 0.5; p<0.01) in female-headed households have low dietary diversity compared to those in male-headed households. Women and children access less diverse diets since 46% and 26%, achieved minimum dietary diversity respectively. Production of vegetables (coef. 0.34; p<0.05) play an important role in improving the dietary diversity of women. Gender (coef. 0.05; p<0.10) and education of the household head (coef. 0.02; p<0.01), food preparation and nutrition training (coef. 0.10; p<0.05) are important factors influencing dietary diversity of the members of a household. Results suggest that there is a need to support community-based programs to provide information on food and the importance of vegetables, their preparation, consumption and utilization to address food and nutrition challenges. Men can contribute towards improving household nutrition security by reducing consumption of food away from the home, especially during periods of food shortages. We recommend the use of complementary quantitative research to determine the patterns and dynamics of men's dietary diversity and compare it with that of other household members.

In low-resource settings, empiric case management of febrile illness is routine as a result of limited access to laboratory diagnostics. The use of comprehensive fever syndromic surveillance, with enhanced clinical microbiology, advanced diagnostics and more robust epidemiologic investigation, could enable healthcare providers to offer a differential diagnosis of fever syndrome and more appropriate care and treatment. We conducted a year-long exploratory study of fever syndrome among patients ≥ 1 year if age, presenting to clinical settings with an axillary temperature of ≥37.5°C and symptomatic onset of ≤5 days. Blood and naso-pharyngeal/oral-pharyngeal (NP/OP) specimens were collected and analyzed, respectively, using AFI and respiratory TaqMan Array Cards (TAC) for multi-pathogen detection of 57 potential causative agents. Furthermore, we examined numerous epidemiologic correlates of febrile illness, and conducted demographic, clinical, and behavioral domain-specific multivariate regression to statistically establish associations with agent detection. From 15 September 2014-13 September 2015, 1007 febrile patients were enrolled, and 997 contributed an epidemiologic survey, including: 14% (n = 139) 1<5yrs, 19% (n = 186) 5-14yrs, and 67% (n = 672) ≥15yrs. AFI TAC and respiratory TAC were performed on 842 whole blood specimens and 385 NP/OP specimens, respectively. Of the 57 agents surveyed, Plasmodium was the most common agent detected. AFI TAC detected nucleic acid for one or more of seven microbial agents in 49% of AFI blood samples, including: Plasmodium (47%), Leptospira (3%), Bartonella (1%), Salmonella enterica (1%), Coxiella burnetii (1%), Rickettsia (1%), and West Nile virus (1%). Respiratory TAC detected nucleic acid for 24 different microbial agents, including 12 viruses and 12 bacteria. The most common agents detected among our surveyed population were: Haemophilus influenzae (67%), Streptococcus pneumoniae (55%), Moraxella catarrhalis (39%), Staphylococcus aureus (37%), Pseudomonas aeruginosa (36%), Human Rhinovirus (25%), influenza A (24%), Klebsiella pneumoniae (14%), Enterovirus (15%) and group A Streptococcus (12%). Our epidemiologic investigation demonstrated both age and symptomatic presentation to be associated with a number of detected agents, including, but not limited to, influenza A and Plasmodium. Linear regression of fully-adjusted mean cycle threshold (Ct) values for Plasmodium also identified statistically significant lower mean Ct values for older children (20.8), patients presenting with severe fever (21.1) and headache (21.5), as well as patients admitted for in-patient care and treatment (22.4). This study is the first to employ two syndromic TaqMan Array Cards for the simultaneous survey of 57 different organisms to better characterize the type and prevalence of detected agents among febrile patients. Additionally, we provide an analysis of the association between adjusted mean Ct values for Plasmodium and key clinical and demographic variables, which may further inform clinical decision-making based upon intensity of infection, as observed across endemic settings of sub-Saharan Africa.