Inhibition of IRE1α-mediated XBP1 mRNA cleavage by XBP1 reveals a novel regulatory process during the unfolded protein response

Background: The mammalian endoplasmic reticulum (ER) continuously adapts to the cellular secretory load by the activation of an unfolded protein response (UPR).  This stress response results in expansion of the ER, upregulation of proteins involved in protein folding and degradation, and attenuation of protein synthesis.  The response is orchestrated by three signalling pathways each activated by a specific signal transducer, either inositol requiring enzyme α (IRE1α), double-stranded RNA-activated protein kinase-like ER kinase (PERK) or activating transcription factor 6 (ATF6).  Activation of IRE1α results in its oligomerisation, autophosphorylation and stimulation of its ribonuclease activity.  The ribonuclease initiates the splicing of an intron from mRNA encoding the transcription factor, X-box binding protein 1 (XBP1), as well as degradation of specific mRNAs and microRNAs. Methods: To investigate the consequence of expression of exogenous XBP1, we generated a stable cell-line expressing spliced XBP1 mRNA under the control of an inducible promotor. Results: Following induction of expression, high levels of XBP1 protein were detected, which allowed upregulation of target genes in the absence of induction of the UPR.  Remarkably under stress conditions, the expression of exogenous XBP1 repressed splicing of endogenous XBP1 mRNA without repressing the activation of PERK. Conclusions: These results illustrate that a feedback mechanism exists to attenuate Ire1α ribonuclease activity in the presence of XBP1

Measuring the degree of integration in the dairy products market in Malawi

Using monthly data for the period 2006⁻2011, this study analyzed the degree of spatial market integration in Malawi focusing on two dairy products (liquid milk and powdered milk) sold in the four major towns of the country. The analysis of spatial market integration is important to assess whether to re-establish a dairy processing facility in the northern part of the country. The empirical analysis comprised of the following steps: (1) Integration between prices from different regions were tested using Johansen’s cointegration procedure, with the results indicating that, in the long run, prices in some areas move in a similar direction. (2) Two spatial equilibrium models were estimated using a three-regime bivariate threshold vector autoregressive model (TVAR) and a three-regime threshold vector error correction model (TVECM). The results showed that transaction costs were not a cause for concern between the areas thus northern Malawi does not need to re-establish a dairy processing facility as surplus areas (mainly Southern Malawi) can supply the region

Colour measurement and colour reproduction systems.

Thesis (M.Sc.Eng.)-University of Natal, Durban, 1987.Techniques of colour measurement and colour reproduction are important in a wide range of commercial and social activities in most modern economies. Their study thus constitutes one of the major areas of interest to the CIE. The project described in this thesis began as an outgrowth of studies of new types of light sources and of the colorimetry of colour-TV systems; plus a conviction that modern TV cameras can operate effectively with a wide range of different illuminating spectra. It was soon evident that two important prerequisites for this research were: an understanding of the processes of human colour vision; and a knowledge of the standard, international, colorimetric terminology of the CIE. These topics are discussed fully in the text. Also included is a review of modern gas-discharge lamps, the~y properties, and their applications. Both high-pressure (HID) types and low-pressure (fluorescent-tube) types are considered. Because of the need to measure the colours of surfaces and their TV reproductions as accurately as possible, various forms of colorimeter were examined, leading to the choice of a spectrophotometer system for this work. The design, construction, and evaluation of an original spetrophotometer system (the UND Spectrophotometer) are described fully in the text. Finally, attention is given to the operation of a television system under nonstandard lighting. Twelve different light sources were evaluated as TV ((taking" illuminants, using both subjective and colorimetric methods of assessment. The experimental results tend to confirm that colorimetric methods are unsuited to colour reproduction evaluation, and that subjective methods are more meaningful. A subjective scale of colour reproduction performance was established, and it was found to correlate closely with the CIE general colour rendering index (Ra) for the various test lamps. The work reported herein predates similar experiments with TV lighting by other workers, and it includes a wider range of light sources. In spite of differences in experimental technique, however, there is broad agreement with their general results

Demand for low carbon food products

The emissions associated with food consumption make up approximately 20-30 percent of Scotland’s total greenhouse gas emissions (GHG). Reducing demand for high carbon footprint food products may provide an effective instrument for reducing GHG emissions. However, there is concern that using consumption based taxes may also have negative consequences on nutrition. Therefore, this thesis investigates the likely effect of carbon consumption taxes on GHG emissions and the resulting impact on nutrient consumption. The data used for the analysis are the Scottish part of Kantar Worldpanel data for the UK for the period 2006-2013 along with various sources of carbon footprint and nutrient data. This thesis models a carbon consumption tax which is based on the carbon footprint of the products of interest. The impact of the taxes on demand for food products were measured through the use of demand systems. Two forms of demand systems were used: Almost Ideal Demand System (AIDS) and an Exact Affine Stone Index (EASI) which allow for the estimation of price elasticities based on time series data. These Marshallian price elasticities were then used for estimating carbon footprint and nutrient elasticities which allow for the estimated change in GHG emissions (represented as carbon emissions) and nutrients. The price elasticities were particularly important for identifying the substitutes and complements of the different food products. This is useful as some food products such as poultry have a lower carbon footprint relative to beef products. The results suggest that applying carbon consumption taxes would likely reduce carbon emissions though the reduction is relatively small. The net effect of taxing all major food products would likely reduce emissions by 543,208.75 tCO2e/y which represents approximately five percent of the total emissions in Scotland attributed to food consumption (no land use change considered). However, taxing only meat and milk food products could reduce emissions by approximately 1.6 million tCO2e/y. While this reduction is much larger than when all food products are taxed, it is considered that modelling all the major food products offers a more realistic understanding of how households will change their demand for the different food products. The effect on nutrient consumption with regards to taxing all food products suggests that households with lower socioeconomic status would likely experience some favourable changes in terms of a reduction in sugar and energy. Though a negative distributional effect is likely to occur when considering the decreased consumption of vitamin D and the increased consumption of salt. Therefore, a carbon consumption tax is estimated to reduce food based GHG emissions by a relatively small amount. Despite the mainly positive effect on nutrient intake, policy makers are still likely to be cautious when considering this instrument because of the relatively small (compared to other studies) reduction in GHG emissions

Impacts of Reducing UK Beef Consumption Using a Revised Sustainable Diets Framework

The impact of beef consumption on sustainability is a complex and evolving area, as sustainability covers many areas from human nutrient adequacy to ecosystem stability. Three sustainability assessment frameworks have been created to help policy makers unpack the complexities of sustainable food systems and healthy sustainable dietary change. However, none of these frameworks have yet to be applied to a case study or individual policy issue. This paper uses a hybrid version of the sustainability assessment frameworks to investigate the impact of reducing beef consumption (with a concurrent increase in consumption of plant-based foods, with a focus on legumes) on sustainability at a UK level. The aim of this paper is to understand the applicability of these overarching frameworks at the scale of an individual policy. Such an assessment is important, as this application of previously high-level frameworks to individual policies makes it possible to summarise, at a glance, the various co-benefits and trade-offs associated with a given policy, which may be of particular value in terms of stakeholder decision-making. We find that many of the proposed metrics found within the sustainability assessment frameworks are difficult to implement at an individual issue level; however, overall they show that a reduction in beef consumption and an increase in consumption of general plant-based foods, with a focus around legumes production, would be expected to be strongly beneficial in five of the eight overarching measures which were assessed