IPASS TECHNICAL MANUAL

Research Methods/ Statistical Methods,

TRACKING THE GOVERNMENT SECTOR IN A NATURAL RESOURCE-BASED ECONOMY

In this paper, we describe the modeling of a resource-dependent economy, namely, Southeast Alaska, in monitoring the impact of federal, state and local government taxing and spending activities on the region. An important part of the modeling effort is construction of a readily accessible regional database for estimating critical economic relationships and variables that provide a baseline forecast series for the region. The Alaska Interactive Policy Analysis Simulation System (IPASS) makes use of the database in assessing the economic impacts of alternative resource management policies on state and local governments. IPASS is a computer-based, user-interactive economic forecasting and simulation system. The basic system is divided into eight modules: investment; final demand; production; regional export; population; labor force; employment; and primary inputs with government being the ninth module. It provides the quantitative framework for measuring and monitoring changes in regional economic activity and, also, for differentiating among the causal factors accounting for these changes. The individual modules form the IPASS shell that makes possible assessment of the effects of specific government activity on each industry and sector in the region's economy and, in turn, the effects of specific industry activity on each level and function of government.Community/Rural/Urban Development, Public Economics,

IMPLAN MODELING APPLICATIONS IN STATE AND REGIONAL DEVELOPMENT

Community/Rural/Urban Development,

Acid-catalysed carboxymethylation, methylation and dehydration of alcohols and phenols with dimethyl carbonate under mild conditions

Dimethyl carbonate (DMC) chemistry has been extended to include acid-catalysed reactions of different aliphatic alcohols and phenols. For the first time, p-toluenesulfonic acid (PTSA), H2SO4, AlCl3 and FeCl3 have been shown to aid carboxymethylation for primary aliphatic alcohols at catalytic loadings with quantitative conversion and selectivity. For carboxymethylation of secondary alcohols, stoichiometric PTSA and catalytic AlCl3 both gave quantitative conversion and selectivity. Stoichiometric FeCl3 and H2SO4 promoted dehydration of linear aliphatic alcohols. Additionally FeCl3 catalysed methylation of cyclohexanol, whilst AlCl3 resulted in methylation of phenolic compounds. This research expands the range of potential application for DMC in green chemistry

Testing Multiple Hypotheses through IMP weighted FDR Based on a Genetic Functional Network with Application to a New Zebrafish Transcriptome Study

In genome-wide studies, hundreds of thousands of hypothesis tests are performed simultaneously. Bonferroni correction and False Discovery Rate (FDR) can effectively control type I error but often yield a high false negative rate. We aim to develop a more powerful method to detect differentially expressed genes. We present a Weighted False Discovery Rate (WFDR) method that incorporate biological knowledge from genetic networks. We first identify weights using Integrative Multi-species Prediction (IMP) and then apply the weights in WFDR to identify differentially expressed genes through an IMP-WFDR algorithm. We performed a gene expression experiment to identify zebrafish genes that change expression in the presence of arsenic during a systemic Pseudomonas aeruginosa infection. Zebrafish were exposed to arsenic at 10 parts per billion and/or infected with P. aeruginosa. Appropriate controls were included. We then applied IMP-WFDR during the analysis of differentially expressed genes. We compared the mRNA expression for each group and found over 200 differentially expressed genes and several enriched pathways including defense response pathways, arsenic response pathways, and the Notch signaling pathway

Challenges in the development of bio-based solvents : A case study on methyl(2,2-dimethyl-1,3-dioxolan-4-yl)methyl carbonate as an alternative aprotic solvent

Many traditional solvents have drawbacks including sustainability and toxicity issues. Legislations such as REACH is driving the move towards less hazardous chemicals and production processes. Therefore, safer bio-based solvents need to be developed. Herein, a 10 step method has been proposed for the development of new bio-based solvents that utilise a combination of in silico modelling of Hansen solubility parameters (HSPs), experimental Kamlet-Abboud-Taft parameters, selection of green synthetic routes followed by applications testing and toxicity measurements. The challenges that the chemical industry face in the development of new bio-based solvents are highlighted through a case study on methyl (2,2-dimethyl-1,3-dioxolan-4-yl) methyl carbonate (MMC) which can be synthesised from glycerol. Although MMC is an attractive candidate as a replacement solvent, simply being bio-derived is not enough for a molecule to be regarded as green. The methodology of solvent development described here is a broadly applicable protocol that will indicate if a new bio-based solvent is functionally proficient, but will also highlight the importance of early stage Kamlet-Abboud-Taft parameters determination and toxicity testing in the development of a green solvent

Application of bio-based solvents for biocatalysed synthesis of amides with Pseudomonas stutzeri lipase (PSL)

Bio-based solvents were investigated for the biocatalysed amidation reactions of various ester-amine combinations by Pseudomonas stutzeri lipase (PSL). Reactions were undertaken in a range of green and potentially bio-based solvents including terpinolene, p-cymene, limonene, 2-methyl THF, ɣ-valerolactone, propylene carbonate, dimethyl isosorbide, glycerol triacetate and water. Solvent screenings demonstrated the importance and potential of using non-polar bio-based solvents for favouring aminolysis over hydrolysis; whilst substrate screenings highlighted the unfavourable impact of reactants bearing bulky para- or 4-substituents. Renewable terpene-based solvents (terpinolene, p-cymene, D-limonene) were demonstrated to be suitable bio-based media for PSL amidation reactions. Such solvents could provide a greener and more sustainable alternative to traditional petrochemical derived non-polar solvents. Importantly, once the enzyme (either PSL or CALB) binds with a bulky para-substituted substrate, only small reagents are able to access the active site. This therefore limits the possibility for aminolysis to take place, thereby promoting the hydrolysis. This mechanism of binding supports the widely accepted 'Ping Pong - Bi Bi' mechanism used to describe enzyme kinetics. The work highlights the need to further investigate enzyme activity in relation to para- or 4-substituted substrates. A priority in PSL chemistry remains a methodology to tackle the competing hydrolysis reaction

A Method of Calculating the Kamlet-Abboud-Taft Solvatochromic Parameters Using COSMO-RS

There is demand for safer and bio-based solvents, brought on by legislation and sustainability objectives. The prediction of physical properties is highly desirable to help design new molecules. Here we present an in silico approach to obtain calculated Kamlet-Abboud-Taft solvatochromic parameters using virtual experiments. The tautomerisation equilibrium of methyl acetoacetate and dimedone was calculated in different solvents with COSMO-RS theory and converted into estimates of solvent dipolarity and hydrogen bond accepting ability, respectively. Hydrogen bond donating ability was calculated as a function of the electron deficient surface area on protic solvents. These polarity descriptors correlate with rate constants and equilibria, and so ability of calculated Kamlet-Abboud-Taft solvatochromic parameters to recreate experimental free energy relationships was tested with sixteen case studies taken from the literature. The accuracy of the calculated parameters was also satisfactory for solvent selection, as demonstrated with a 1,4-addition reaction and a multicomponent heterocycle synthesis