Spherical shield Patent

Flexible bellows joint shielding sleeve for propellant transfer pipeline

An assessment of sphere drag coefficient data

Wind tunnel test data for falling sphere drag coefficient determinatio

Wind tunnel calibration of the ''Arcasonde 1-A'' at simulated altitudes between 35 and 57 km

Subsonic wind tunnel calibration of Arcasonde 1-A atmospheric temperature sensing unit at simulated altitudes between 35 and 56 k

Social inequality and children's growth in Guatemala

This paper is an investigation of the effects of social inequality in Guatemala on children’s health and nutritional status as measured by attained height. Guatemala remains a highly stratified and poor society. We examine the association of land distribution, land tenure, occupation, and other aspects of family social and economic status with children’s height between the ages of three months and 36 months, using data from a cross-sectional survey. An important consequence of the poverty and poor living conditions of the majority of the Guatemalan population is substantial deficits in children’s growth. Our results suggest that children’s growth is affected by ethnicity, their father’s occupation, land distribution in the area where they live, and maternal education. Substantial growth deficits are observed among children living at altitudes above 1500 metres; we hypothesize that this is because, in Guatemala, higher altitude is associated with land scarcity, poorer agricultural conditions, and greater remoteness from transport networks and other public services

Childhood immunization and pregnancy-related services in Guatemala

In this paper we examine the experience of one poor country, Guatemala, that provided childhood immunization partly through a major national campaign, and provided pregnancyrelated services through government health facilities, during the 1980s. Specifically, we compare the breadth of coverage of these two types of services using national sample survey data collected in 1987. We then draw upon results of previous qualitative studies to explore the social, cultural, and organizational factors that may account for differences between the use of immunization and the use of pregnancy-related health services

Preparation and thermal characterisation of poly(lactic acid) nanocomposites prepared from organoclays based on an amphoteric surfactant

New polymer-clay nano-composites composed of poly(lactic acid) and a novel organoclay based on cocamidopropylbetaine (CAB) and sodium montmorillonite (MMT) were prepared by solution casting and characterised by X-Ray Diffraction Analysis (XRDA), Transmission Electron Microscopy (TEM) and Thermogravimetric Analysis (TGA). A similar series of composites based on PLA and Cloisite 30B, a commercially available organoclay, were prepared for comparison. The thermal stability of the CAB-MMT organoclays decreased with increasing surfactant loading. Experimental organoclays with an organic content similar to that of the commercial organoclay were found to be of comparable thermal stability. XRDA analysis of the PLA-organoclay nano-composites showed that PLA intercalated the gallery space of both types of organoclay to similar extents and the increased spacing was confirmed by TEM. The thermal stabilities of the PLA-organoclay composites based on CAB-MMT were higher than those based on the commercial organoclay

Suppression of Ornithine Decarboxylase Gene Expression by Retinoids in Cultured Human Keratinocytes

Modulation of ornithine decarboxylase (ODC) gene expression by retinoids was analyzed in human keratinocyte cultures maintained in serum-free medium containing 0.15mM Ca++. Cells were incubated with all-trans-retinoic acid, 13-cis-retinoic acid or arotinoid Ro15-0778 (10−10 to 10−5 M), total RNA was isolated, and mRNA transcripts for ODC were analyzed by Northern and slot blot hybridizations with a human ODC cDNA. Treatment of cells for 24h resulted in a dose-dependent decrease in ODC mRNA levels, with an estimated IC50 of ∼1 × 10−8 M for all-trans- and 13-cis-retinoic acid, while Ro15-0778 was somewhat less effective (IC50 ∼1-5 × 10−7 M). The suppression of ODC mRNA levels by retinoids was detectable at ∼3h of incubation, with essentially a maximal inhibition at 12h. Reduced ODC mRNA levels noted after 24h of incubation with 5 × 10−7 M all-trans-retinoic acid were accompanied by a reduction in ODC enzyme activity. To determine if all-trans-retinoic acid was regulating ODC gene expression directly, or if protein synthesis was required, ODC expression was analyzed in cultures treated with protein synthesis inhibitors. In the presence of cycloheximide or puromycin, all-trans-retinoic acid did not suppress ODC mRNA levels. These findings suggest that suppression of ODC gene expression is not a direct effect of all-trans-retinoic acid, but depends on ongoing protein synthesis

The Relationship of Eccentric Hamstrings Time to Peak Torque and Anterior Knee Joint Displacement

Research suggests that females are more likely to sustain an anterior cruciate ligament (ACL) injury when compared to males and that the ACL and hamstring muscles work together to preserve joint stability. Information is limited regarding any relationship between anterior knee joint laxity, in the absence of injury, and eccentric hamstring time to peak torque. This study compared anterior knee joint displacement and eccentric hamstrings time to peak torque in 30 female athletes and 30 female non-athletes ages 14-18 years. The passive anterior drawer was measured on both lower extremities using the KT-1000® arthrometer before and after eccentric hamstrings time to peak torque testing on the Biodex® System 2 isokinetic dynamometer. Data were collected at two speeds, 90°/second and 150°/second. Results of this study suggest there is no relationship between eccentric hamstrings time to peak torque and anterior knee joint displacement in the two populations tested