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Marker-trait association studies in tomato have progressed rapidly due to the availability of several populations developed between wild species and domesticated tomato. However, in the absence of whole genome sequences for each wild species, molecular marker methods for whole genome comparisons and fine mapping are required. We describe the development and validation of a diversity arrays technology (DArT) platform for tomato using an introgression line (IL) population consisting of wild Solanum pennellii introgressed into Solanum lycopersicum (cv. M82). A tomato diversity array consisting of 6,912 clones from domesticated tomato and twelve wild tomato/Solanaceous species was constructed. We successfully bin-mapped 990 polymorphic DArT markers together with 108 RFLP markers across the IL population, increasing the number of markers available for each S. pennellii introgression by tenfold on average. A subset of DArT markers from ILs previously associated with increased levels of lycopene and carotene were sequenced, and 44% matched protein coding genes. The bin-map position and order of sequenced DArT markers correlated well with their physical position on scaffolds of the draft tomato genome sequence (SL2.40). The utility of sequenced DArT markers was illustrated by converting several markers in both the S. pennellii and S. lycopersicum phases to cleaved amplified polymorphic sequence (CAPS) markers. Genotype scores from the CAPS markers confirmed the genotype scores from the DArT hybridizations used to construct the bin map. The tomato diversity array provides additional “sequence-characterized” markers for fine mapping of QTLs in S. pennellii ILs and wild tomato species.

Thesis (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; and, (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; in conjunction with the Leaders for Global Operations Program at MIT, 2010., Cataloged from PDF version of thesis., Includes bibliographical references (p. 63-66)., Wave-based picking systems have been used as the standard for warehouse order fulfillment for many years. Waveless picking has emerged in recent years as an alternative pick scheduling system, with proponents touting the productivity and throughput gains within such a system. This paper analyzes in more depth the differences between these two types of systems, and offers insight into the comparative advantages and disadvantages of each. While a select few pieces of literature perform some analyses of wave vs. waveless picking, this paper uses a case-study of a waveless picking system in an Amazon.com fulfillment center as a model for how to manage a waveless system once it has been adopted. Optimization methods for decreasing chute-dwell time and increasing throughput by utilizing tote prioritization are also performed using discrete-simulation modeling. The analysis concludes that managing waveless picking warehouse flow by controlling the allowable quantity of partially picked orders to match downstream chute capacity can lead to reduced control over cycle times and customer experience. Suggestions are also made on possible future research for how to optimally implement a cycle-time controlled system., by G. Todd Bishop., M.B.A., S.M.

Vale Inco's Pressure Oxidative Leach (POL) process was developed to treat nickel concentrates from the Voisey's Bay project in northern Labrador, Canada. The process eliminates the need for a pyrometallurgical treatment stage, improving metal recoveries and reducing capital and operating costs. It also eliminates the dust and gas emissions associated with smelting, and recovers most of the iron and sulphur in the concentrate as haematite and elemental sulphur respectively. The process was developed at a pilot plant scale (1:10 000) in 2003-04 at the Mississauga R&D facility, and then at a demonstration plant scale (1:100) in 2005-2008 at Argentia, Newfoundland. The technological advances made and lessons learnt during the operation of the demonstration plant are outlined, in such areas as metal recoveries, process parameters, and equipment design. There is a description of the process, which includes leaching, solvent extraction and electrowinning stages, together with a flowsheet., Vale Inco's Pressure Oxidative Leach (POL) process was developed to treat nickel concentrates from the Voisey's Bay project in northern Labrador, Canada. The process eliminates the need for a pyrometallurgical treatment stage, improving metal recoveries and reducing capital and operating costs. It also eliminates the dust and gas emissions associated with smelting, and recovers most of the iron and sulphur in the concentrate as haematite and elemental sulphur respectively. The process was developed at a pilot plant scale (1:10 000) in 2003-04 at the Mississauga R&D facility, and then at a demonstration plant scale (1:100) in 2005-2008 at Argentia, Newfoundland. The technological advances made and lessons learnt during the operation of the demonstration plant are outlined, in such areas as metal recoveries, process parameters, and equipment design. There is a description of the process, which includes leaching, solvent extraction and electrowinning stages, together with a flowsheet.

The use of hydrated lime has the potential to be an effective in situ technology for the destruction and containment of explosives contamination. This was proven with the results from the SERDP project CU-1230, where it was shown to rapidly degrade RDX and TNT. However, prior to field deployment of this technology additional experimental work was required to address concerns regarding the mechanism of the alkaline hydrolysis reaction, the character of the final products of the reaction, the potential for biodegradation of the reaction products, and the amount of lime required for alkaline hydrolysis in different soils. The results can be summarized as follows. First, spectroscopic studies of the TNT alkaline hydrolysis reaction identified two well-resolved and spectrally distinct reaction intermediates. A single radical species was formed during the TNT hydroxide reaction that correlated with the second reaction intermediate. Second, TNT and RDX degraded rapidly through alkaline hydrolysis at pH 12.5. The end products of the reaction were low water-soluble molecular weight compounds that included nitrate and format. No polymer formation was observed under these reaction conditions. Third, anaerobic and aerobic incubation of neutralized hydrolysis reaction mixtures with range soil showed that there is a high potential for biodegradation. This was evidenced by mineralization of reaction end products (production of [14C]-labeled carbon dioxide) and a decrease in nitrite and nitrate concentrations. Fourth, a simple method to predict the lime required by different soils under different environmental and contamination conditions was developed based on current ASTM methods for raising soil pH. A guidance document was prepared to provide site managers a means to easily and inexpensively determine the lime dosage required to raise pH to levels required for munitions and metals remediation., The original document contains color images.

The genome of tomato (Solanum lycopersicum) is being sequenced by an international consortium of 10 countries (Korea, China, the United Kingdom, India, The Netherlands, France, Japan, Spain, Italy and the United States) as part of a larger initiative called the International Solanaceae Genome Project (SOL): Systems Approach to Diversity and Adaptation. The goal of this grassroots initiative, launched in November 2003, is to establish a network of information, resources and scientists to ultimately tackle two of the most significant questions in plant biology and agriculture: (1) How can a common set of genes/proteins give rise to a wide range of morphologically and ecologically distinct organisms that occupy our planet? (2) How can a deeper understanding of the genetic basis of plant diversity be harnessed to better meet the needs of society in an environmentally friendly and sustainable manner? The Solanaceae and closely related species such as coffee, which are included in the scope of the SOL project, are ideally suited to address both of these questions. The first step of the SOL project is to use an ordered BAC approach to generate a high quality sequence for the euchromatic portions of the tomato as a reference for the Solanaceae. Due to the high level of macro and micro-synteny in the Solanaceae the BAC-by-BAC tomato sequence will form the framework for shotgun sequencing of other species. The starting point for sequencing the genome is BACs anchored to the genetic map by overgo hybridization and AFLP technology. The overgos are derived from approximately 1500 markers from the tomato high density F2-2000 genetic map (http://sgn.cornell.edu/). These seed BACs will be used as anchors from which to radiate the tiling path using BAC end sequence data. Annotation will be performed according to SOL project guidelines. All the information generated under the SOL umbrella will be made available in a comprehensive website. The information will be interlinked with the