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Africa is the second largest continent in terms of size and population.1,2With approximately 1.256 billion people (about 15% of the world’s population) and a land area of 30.3 million square kilometers (including adjacent islands), it occupies about 20.4% of the earth’s total land area.1A significant fraction of the people in the Caribbean* and South America are of African descent, and there are many historical and cultural links among the people of these regions.3South America has 422.5 million people, and the Caribbean has about 39.12 million people;1hence, the total population of all three areas represents about 20% of the world’s population.1,2Similarities in climate also mean that common approaches can be explored for establishing sustainable building materials, and the range of development indices offer unique opportunities for collaborations in research and education that can facilitate human development.4

This paper presents the result of an experimental study of the corrosion behavior of epoxy-coated steel specimens. The spray-coated X65 steel samples were immersed in HCL solutions with varying pH levels. The effects of water adsorption and corrosion were studied via weight gain measurements and microscopic studies. The initial adsorption of fluid resulted in increasing weight gain prior to the weight loss that followed the onset of film delamination/debonding. The underlying mechanisms of corrosion are also elucidated for the steel substrate at different stages of exposure. The delamination is modeled using fracture mechanics concepts and discussing the implication of the current work for robust pipeline design.

We examine the fundamental operation of an Organic Light Emitting Device with emphasis laid on the Hole Transport Layer (HTL) and the optoelectronic properties of the other layers that make up the device. Investigation of the adhesion properties together with surface morphology, electrical and optical characterization of the different layers of the device was carried out. Poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT: PSS) was used as the conventional HTL material in the first case. This yields the reference device or system under studies. In the second case, PEDOT: PSS was replaced by an inorganic material, molybdenum trioxide (MoO 3 ). The device performance in case two (2) revealed an improvement in performance. A couple of deposition techniques were examined together with the analysis of their effect on the resultant device properties. With the aid of theoretical models, we quantified the results obtained in terms of average pull-off forces and corresponding adhesion energies. The Derjaguin-Muller-Toporov model was utilized to model the adhesion energies between interfaces of adjacent layers of the device. Results that delineate modeling of charge transport across device interfaces are shown including the effects of pressure on the device optoelectronic properties.

The World Bank estimates that over two billion people on the planet live their daily lives without access to basic, reliable electric services. Rural populations in Africa, Latin America, Asia, and island nations need clean water, health services, communications, and light at night. Small, simple, solar electric systems are part of the solution—increasing the quality of life, often at a cost that is less than what is presently being spent for kerosene, dry-cell batteries, and the recharging of automotive batteries that must be lugged to the nearest town on a weekly basis (see Figure 1).

Targeted delivery of superparamagnetic iron oxide nanoparticles (SPIONs) could facilitate their accumulation in metastatic cancer cells in peripheral tissues, lymph nodes and bones and enhance the sensitivity of magnetic resonance imaging (MRI). The specificities of luteinizing hormone releasing hormone (LHRH) and luteinizing hormone/chorionic gonadotropin (LH/CG)- bound SPIONs were tested in human breast cancer cells in vitroand were found to be dependent on the receptor expression of the target cells, the time of incubation and showed saturation kinetics. In incubations with MDA-MB-435S.luc cells, the highest iron accumulation was 452.6 pg Fe/cell with LHRH-SPIONs, 203.6 pg Fe/cell with β-CG-SPIONs and 51.3 pg Fe/cell with SPIONs. Incubations at 4 °C resulted in 1.1 pg Fe/cell. Co-incubation with the same ligands (βCG or LHRH) decreased the iron accumulation in each case. LHRH-SPIONs were poorly incorporated by macrophages. Tumors and metastatic cells from breast cancer xenografts were targeted in vivoin a nude mouse model. LHRH-SPION specifically accumulated in cells of human breast cancer xenografts. The amount of LHRH-SPION in the lungs was directly dependent on the number of metastatic cells and amounted to 77.8 pg Fe/metastastic cell. In contrast, unconjugated SPIONs accumulated in the liver, showed poor affinity to the tumor, and were not detectable in metastatic lesions in the lungs. LHRH-SPION accumulated in the cytosolic compartment of the target cells and formed clusters. LHRH-SPIONs did not accumulate in livers of normal mice. In conclusion, LHRH conjugated SPIONs may serve as a contrast agent for MR imaging in vivoand increase the sensitivity for the detection of metastases and disseminated cells in lymph nodes, bones and peripheral organs.Targeted delivery of superparamagnetic iron oxide nanoparticles (SPIONs) could facilitate their accumulation in metastatic cancer cells in peripheral tissues, lymph nodes and bones and enhance the sensitivity of magnetic resonance imaging (MRI). The specificities of luteinizing hormone releasing hormone (LHRH) and luteinizing hormone/chorionic gonadotropin (LH/CG)- bound SPIONs were tested in human breast cancer cells in vitroand were found to be dependent on the receptor expression of the target cells, the time of incubation and showed saturation kinetics. In incubations with MDA-MB-435S.luc cells, the highest iron accumulation was 452.6 pg Fe/cell with LHRH-SPIONs, 203.6 pg Fe/cell with β-CG-SPIONs and 51.3 pg Fe/cell with SPIONs. Incubations at 4 °C resulted in 1.1 pg Fe/cell. Co-incubation with the same ligands (βCG or LHRH) decreased the iron accumulation in each case. LHRH-SPIONs were poorly incorporated by macrophages. Tumors and metastatic cells from breast cancer xenografts were targeted in vivoin a nude mouse model. LHRH-SPION specifically accumulated in cells of human breast cancer xenografts. The amount of LHRH-SPION in the lungs was directly dependent on the number of metastatic cells and amounted to 77.8 pg Fe/metastastic cell. In contrast, unconjugated SPIONs accumulated in the liver, showed poor affinity to the tumor, and were not detectable in metastatic lesions in the lungs. LHRH-SPION accumulated in the cytosolic compartment of the target cells and formed clusters. LHRH-SPIONs did not accumulate in livers of normal mice. In conclusion, LHRH conjugated SPIONs may serve as a contrast agent for MR imaging in vivoand increase the sensitivity for the detection of metastases and disseminated cells in lymph nodes, bones and peripheral organs.

AbstractThis paper presents the results of numerical simulations and experimental measurements of temperature distributions in heat-affected zones formed during inertia welding. These were obtained from the inertia welding of Inconel 718 (IN718) toIN718 and the inertia welding of IN718 to 1045 Steel. Microstructures of the heat-affected zone are presented along with microhardness profiles for similar and dissimilar inertia welds. The measured temperature profiles are compared with numerical/finite element predictions of temperature distributions in the heat-affected zone. The effects of friction welding parameters on the temperature distributions in the heat-affected zone are modeled using the finite element method. The experimental results are compared with predictions from numerical analysis. The implications of the results are then discussed.