The AGRHYMET data communications project

The U.S. Geological Survey (USGS) and the U.S. Agency for International Development (USAID) are providing technical assistance to the AGRHYMET program in West Africa. AGRHYMET staff use remote sensing technology to produce satellite image maps of the Sahel region of West Africa. These image maps may show vegetation greenness, sea surface temperatures, or processed weather satellite imagery. The image maps must be distributed from the AGRHYMET Regional Center in Niger to national AGRHYMET centers in the member countries of Burkina Faso, Cape Verde, Chad, Gambia, Guinea-Bissau, Mali, Mauritania, Niger, and Senegal. After consideration of a number of land- and space-based solutions for image map distribution, the best solution was determined to be use of International Maritime Satellite Organization (INMARSAT) land-based terminals. In April 1992, a field test and proof-of-concept demonstration using land-mobile terminals produced favorable results. The USGS and USAID are setting up a wide area network using INMARSAT terminals to link the AGRHYMET sites for image data transfer. The system is in the procurement and installation phase and initial opening capability may be operational for the 1993 growing season, starting in May 1993

Removing rubidium using potassium cobalt hexacyanoferrate in the membrane adsorption hybrid system

© 2017 Elsevier B.V. Highly-priced rubidium (Rb) can be effectively extracted from seawater using potassium cobalt hexacyanoferrate (KCoFC) and ammonium molybdophosphate (AMP) adsorbents in the membrane adsorption hybrid system (MAHS). KCoFC (<0.075 mm), KCoFC (0.075–0.15 mm), and AMP (<0.075 mm) had Langmuir adsorption capacities of 145, 113, and 77 mg/g at pH 6.5–7.5, respectively. When KCoFC (<0.075 mm) at a dose of 0.2 g/L was initially added to 4 L of a solution containing 5 mg Rb/L in the MAHS and 25% of the initial dose was repeatedly added every hour, the amount of Rb removed remained steady at 90–96% for the experiment's 26 h duration. The removal of Rb by AMP under similar conditions was 80–82%. The cumulative Rb removed by KCoFC (<0.075 mm) in MAHS was only 33% reduced in the presence of high concentrations of other cations in synthetic seawater compared to that in solution containing only Rb. Approximately 30% of the adsorbed Rb was desorbed using 1 M KCl. When the desorbed solution was passed through a column containing resorcinol formaldehyde (RF), 35% of the Rb in the desorbed solution was adsorbed on RF. Furthermore 50% of the Rb adsorbed on RF was recovered by 1 M HCl leaching of the column. This sequence of concentration and separation of Rb in the presence of other cations in synthetic seawater is an efficient method for recovering pure Rb from real seawater and seawater reverse osmosis brine

Submerged membrane filtration adsorption hybrid system for the removal of organic micropollutants from a water reclamation plant reverse osmosis concentrate

© 2016 Elsevier B.V. Reverse osmosis (RO) is a widespread water treatment process utilised in water reuse applications. However, the improper discharge of RO concentrate (ROC) containing organic micropollutants such as pharmaceuticals into the environment may cause potential health risks to non-target species and particularly those in aquatic environments. A study was conducted using a submerged membrane-filtration/granular activated carbon (GAC) adsorption hybrid system to remove organic micropollutants from a water treatment plant ROC by initially adding 10 g GAC /L of membrane reactor volume with 10% daily GAC replacement. The percentage of dissolved organic carbon removal varied from 60% to 80% over an operation lasting 10 days. Removal of organic micropollutants was almost complete for virtually all compounds. Of the 19 micropollutants tested, only two remained (the less hydrophobic DEET 27 ng/L and the hydrophilic sulfamethoxazole 35 ng/L) below 80% removal on day 1, while five of the most hydrophobic micropollutants were detectable in very small concentrations ( 89%–> 99% being removed. High percentages of micropollutants were removed probably because of their high hydrophobicity or they had positive or neutral charges and therefore they were electrostatically adsorbed to the negatively charged GAC

The origin of late archaean granitoids in the Sukumaland greenstone belt of Northern Tanzania: geochemical and isotopic constraints

Granitoids intruding the late Archaean sequences of the Sukumaland Greenstone Belt of northern Tanzania belong to two distinct geochemical suites. Suite 1 is characterised by Na2O/K2O > 1 (1.04 – 4.67), high Sr/Y (56 – 204) and Ba/Rb ratios (6.1 – 27.1) and low Rb/Sr ratios (0.08 - 0.25). The rocks are enriched in Sr (405 – 1264 ppm) and depleted in Yb (0.17 – 0.93 ppm) and Rb (56 – 132 ppm). On chondrite-normalised REE diagrams, the rocks display highly fractionated patterns characterised by relative LREE enrichment ((La/Yb)N = 23 – 128 and (Gd/Yb)N = 3.10 – 8.54) and lower concentrations of the HREE (YbN = 0.80 – 4.45). On primitive mantle-normalised spidergrams, Nb and Ti, together with P and Y are depleted relative to adjacent elements. The major and trace element characteristics of Suite 1 are comparable to those of typical Archaean TTG suites and High Silica Adakites (HSA). Suite 2 granitoids are characterised by Na2O/K2O < 1, low Sr/Y (2.80 – 41.7) and Ba/Rb (0.40 – 8.91) ratios and high Rb/Sr (0.30 – 6.27) ratios. Suite 2 is also characterised by low Sr (53 - 326 ppm) and high Rb (40 - 365 ppm) and Yb (0.44 – 1.36 ppm) contents. Compared to Suite 1, Suite 2 rocks display less fractionated REE patterns ((La/Yb)N = 15 – 86 and (Gd/Yb)N = 1.73 – 6.74) and are characterised by higher concentrations of the HREE (YbN = 2.1 – 6.5). On primitive mantle-normalised spidergrams, Suite 2 samples, like those of Suite 1, show relative depletion in Th, Nb and Ti, together with P and Y relative to adjacent elements. Sm-Nd mean crustal residence ages for both suites are indistinguishable and range between 2470 and 2720 Ma with a mean of 2610 &#61617; 35 Ma (2 SE), similar to the emplacement age of 2620 &#61617; 40 Ma. The granitoids are interpreted to have formed by partial melting at the base of a late Archaean thickened sub-arc basaltic crust. Melting to form the Suite 1 granitoids occurred in the eclogite stability field whereas Suite 2 formed by melting at shallower depth in the garnet amphibolite stability field. Tanzania Journal of Science Vol. 32 (1) 2006: pp. 75-8

Financial stability and the Trans-Pacific Partnership: lessons from Chile and Malaysia

This repository item contains a working paper from the Boston University Global Economic Governance Initiative. The Global Economic Governance Initiative (GEGI) is a research program of the Center for Finance, Law & Policy, the Frederick S. Pardee Center for the Study of the Longer-Range Future, and the Frederick S. Pardee School of Global Studies. It was founded in 2008 to advance policy-relevant knowledge about governance for financial stability, human development, and the environment.There is growing recognition that nations may need to deploy cross-border financial regulations to prevent and mitigate financial crises. Indeed, in December of 2012 the International Monetary Fund (IMF) agreed on a new ‘institutional view’ that notes how the IMF will begin to recommend that nations deploy cross-border financial regulations going forward. However, many nations have become party to global, regional, and bi-lateral trade and investment treaties that may restrict their ability to effectively deploy such regulations. This paper examines the cases of two countries currently in negotiations for a Trans-Pacific Partnership Agreement (TPP): Chile and Malaysia. The paper examines the extent to which each nation has deployed cross-border financial regulations in the past, and the extent to which they have negotiated the policy space for such regulations in its previous trade and investment treaties. Finally, it analyzes the extent to which such measures would be permitted if the TPP’s investment provisions looked like the model bi-lateral investment treaty of the United States. We find that, with some important exceptions, both countries have successfully deployed crossborder financial regulations and have carved out the ability to do so under a sample of representative trading commitments. However, such policy space would be jeopardized if the TPP conformed to the US model rather than arrangements that each country has been able to broker in other arenas

Functional characterization of macrophage receptors for in vitro phagocytosis of unopsonized Pseudomonas aeruginosa

The phagocytic receptor for unopsonized Pseudomonas aeruginosa was characterized functionally using human monocyte-derived macrophages. Freshly isolated human peripheral blood monocytes were unable to ingest unopsonized P. aeruginosa; ingestion did not occur until the cells had been in culture for 2 d and it became maximal after 4 d. Macrophages plated on coverslips derivatized with anti-BSA IgG or with human gamma-globulin lost the capacity to phagocytose unopsonized P. aeruginosa, unopsonized zymosan, and EIgG but bound C3bi-coated erythrocytes normally. Each of the four human IgG subclasses and Fc fragments of anti-BSA IgG inhibited phagocytosis of both unopsonized P. aeruginosa and EIgG. Phagocytosis of P. aeruginosa and zymosan was markedly impaired and EIgG minimally inhibited if macrophages were plated on coverslips derivatized with mannan or when mannan was added to the phagocytosis buffer. Phagocytosis of P. aeruginosa and zymosan, and binding of EC3bi was dependent on the presence of divalent cations, but phagocytosis of EIgG was not. The macrophage phagocytic receptor for unopsonized P. aeruginosa was inactivated by proteolytic enzymes. Phagocytosis of P. aeruginosa was inhibited by D-mannose, L-fucose, and alpha methyl mannoside, but not by L-mannose, D-fucose, or D-glucose. The same sugars inhibited phagocytosis of unopsonized zymosan. We conclude that phagocytosis of unopsonized P. aeruginosa by human monocyte-derived macrophages is facilitated by mannose receptors

Functional characterization of macrophage receptors for in vitro phagocytosis of unopsonized Pseudomonas aeruginosa

The phagocytic receptor for unopsonized Pseudomonas aeruginosa was characterized functionally using human monocyte-derived macrophages. Freshly isolated human peripheral blood monocytes were unable to ingest unopsonized P. aeruginosa; ingestion did not occur until the cells had been in culture for 2 d and it became maximal after 4 d. Macrophages plated on coverslips derivatized with anti-BSA IgG or with human gamma-globulin lost the capacity to phagocytose unopsonized P. aeruginosa, unopsonized zymosan, and EIgG but bound C3bi-coated erythrocytes normally. Each of the four human IgG subclasses and Fc fragments of anti-BSA IgG inhibited phagocytosis of both unopsonized P. aeruginosa and EIgG. Phagocytosis of P. aeruginosa and zymosan was markedly impaired and EIgG minimally inhibited if macrophages were plated on coverslips derivatized with mannan or when mannan was added to the phagocytosis buffer. Phagocytosis of P. aeruginosa and zymosan, and binding of EC3bi was dependent on the presence of divalent cations, but phagocytosis of EIgG was not. The macrophage phagocytic receptor for unopsonized P. aeruginosa was inactivated by proteolytic enzymes. Phagocytosis of P. aeruginosa was inhibited by D-mannose, L-fucose, and alpha methyl mannoside, but not by L-mannose, D-fucose, or D-glucose. The same sugars inhibited phagocytosis of unopsonized zymosan. We conclude that phagocytosis of unopsonized P. aeruginosa by human monocyte-derived macrophages is facilitated by mannose receptors

High-k Dielectric Thickness and Halo Implant on Threshold Voltage Control

High-k dielectric oxides have been used to replace the widely used silicon dioxide (SiO2) gate dielectrics to overcome physical limits of transistor scaling. The thickness of high-k gate dielectric influences the threshold voltage (VTH) and off-state leakage current (IOFF). A device with high drive current (ION) and low IOFF gives a high on-off current ratio (ION/IOFF), which leads to a faster switching speed for the Ntype Metal Oxide Semiconductor Field Effect Transistor (NMOS). In order to achieve the best ION/IOFF ratio for a predetermined range of VTH, halo implant was used to adjust the threshold voltage. The finding shows that optimum VTH and ION/IOFF ratio can be achieved by selecting the most suitable halo implant dose in a virtually fabricated 14nm gate-length La2O3-based NMOS device with varying high-k dielectric oxide thickness