Proprotein convertases in amphioxus: predicted structure and expression of proteases SPC2 and SPC3.

SPC2 and SPC3 are two members of a family of subtilisin-related proteases which play essential roles in the processing of prohormones into their mature forms in the pancreatic B cell and many other neuroendocrine cells. To investigate the phylogenetic origins and evolutionary functions of SPC2 and SPC3 we have identified and cloned cDNAs encoding these enzymes from amphioxus (Branchiostoma californiensis), a primitive chordate. The amino acid sequence of preproSPC2 contains 689 aa and is 71% identical to human SPC2. In contrast, amphioxus prproSPC3 consists of 774 aa and exhibits 55% identity to human SPC3. These results suggest that the primary structure of SPC2 has been more highly conserved during evolution than that of SPC3. To further investigate the function(s) of SPC2 and SPC3 in amphioxus, we have determined the regional expression of these genes by using a reverse transcriptase-linked polymerase chain reaction (RT-PCR) assay. Whole amphioxus was dissected longitudinally into four equal-length segments and RNA was extracted. Using RT-PCR to simultaneously amplify SPC2 and SPC3 DNA fragments, we found that the cranial region (section 1) expressed equal amounts of SPC2 and SPC3 mRNAs, whereas in the caudal region (section 4) the SPC2-to-SPC3 ratio was 5:1. In the mid-body sections 2 and 3 the SPC2-to-SPC3 ratio was 1:5. By RT-PCR we also determined that amphioxus ILP, a homologue of mammalian insulin/insulin-like growth factor, was expressed predominately in section 3. These results suggest that the relative levels of SPC2 and SPC3 mRNAs are specifically regulated in various amphioxus tissues. Furthermore, the ubiquitous expression of these mRNAs in the organism indicates that they are involved in the processing of other precursor proteins in addition to proILP.

Hepatic expression of mature transforming growth factor beta 1 in transgenic mice results in multiple tissue lesions.

Aberrant expression of transforming growth factor beta 1 (TGF-beta 1) has been implicated in a number of disease processes, particularly those involving fibrotic and inflammatory lesions. To determine the in vivo effects of overexpression of TGF-beta 1 on the function and structure of hepatic as well as extrahepatic tissues, transgenic mice were generated containing a fusion gene (Alb/TGF-beta 1) consisting of modified porcine TGF-beta 1 cDNA under the control of the regulatory elements of the mouse albumin gene. Five transgenic lines were developed, all of which expressed the Alb/TGF-beta 1 transgene selectively in hepatocytes. The transgenic line 25 expressing the highest level of the transgene in the liver also had high (> 10-fold over control) plasma levels of TGF-beta 1. Hepatic fibrosis and apoptotic death of hepatocytes developed in all the transgenic lines but was more pronounced in line 25. The fibrotic process was characterized by deposition of collagen around individual hepatocytes and within the space of Disse in a radiating linear pattern. Several extrahepatic lesions developed in line 25, including glomerulonephritis and renal failure, arteritis and myocarditis, as well as atrophic changes in pancreas and testis. The results from this transgenic model strongly support the proposed etiological role for TGF-beta 1 in a variety of fibrotic and inflammatory disorders. The transgenic model may also provide an appropriate paradigm for testing therapeutic interventions aimed at neutralizing the detrimental effects of this important cytokine.

Agings and the parameters in static postural way

There is strong scientific evidence from research trials that aging is associated with loss of muscle mass and decline of neuromuscular abilities. Postural stability is an important neuromuscular ability for the maintenance of upright posture as well as maintaining equilibrium or balance while performing movements and everyday activities. Postural stability is also an important factor in elderly people where postural instability is a major contributor to falls. In our study young and elderly subjects stood quietly in upright posture with parallel positions of their feet and opened eyes on a force platform and performed 3 trials with each trial lasting 30 s. The effects of healthy aging on postural sway parameters were studied. We found that age-related changes in postural sway mostly affect the velocity of the center of pressure movement and the mean amplitude center of pressure movement during static postural sway test.

Boston, Massachusetts, 2-Dimensional Building Footprints with Height Data (from LIDAR data), 2002

This dataset consists of 2D footprints of the buildings in the metropolitan Boston area, based on tiles in the orthoimage index (orthophoto quad ID: 229890, 229894, 229898, 229902, 233886, 233890, 233894, 233898, 233902, 237890, 237894, 237898, 237902, 241890, 241894, 241898, 241902, 245898, 245902). This data set was collected using 3Di's Digital Airborne Topographic Imaging System II (DATIS II). Roof height and footprint elevation attributes (derived from 1-meter resolution LIDAR (LIght Detection And Ranging) data) are included as part of each building feature. This data can be combined with other datasets to create 3D representations of buildings and the surrounding environment.

Rural Labour Market Developments in the Former Yugoslav Republic of Macedonia. Factor Markets Working Paper No. 5, September 2011

The significant changes in the quantitative and qualitative characteristics of human resources in rural Macedonia can be explained by the continued trend of emigration from villages to urban areas and abroad. The intensity of emigration has altered the demographic structure and reproductive base of the rural population, along with the income of rural households. The rural and agricultural labour market faces a mismatch with respect to the unfavourable age, education and spatial distribution of the total labour force. A reduction in the participation of women in the agricultural labour force is a new feature. The overall transformation is apparent in the income structure of rural households. An increase in the share of households with mixed income sources notably stems from households that receive remittances and foreign currency funds from family members abroad. The demographic revitalisation of rural areas depends on economic revitalisation, with a more rational use of the labour force and human resources, as well as a restructuring of agricultural production and agricultural holdings. In addition, improvements are necessary in the functioning of market institutions to better meet the needs of smaller farmers and the rural economy.

Ownership and Investment Behaviour in Transition Countries: A Case Study of Collective and Corporate Farms in the Czech Republic. Factor Markets Working Paper No. 17, February 2012

Cooperative and corporate farms have retained an important role for agricultural production in many transition countries of Central and Eastern Europe. Despite this importance, these farms' ownership structure, and particularly the ownership's effect on their investment activity, which is vital for efficient restructuring and the sector's future development, are still not well understood. This paper explores the ownership-investment relationship using data on Czech farms from 1997 to 2008. We allow for ownership-specific variability in farm investment behaviour analyzed by utilizing an error-correction accelerator model. Empirical results suggest significant differences in the level of investment activity, responsiveness to market signals, investment lumpiness, as well as investment sensitivity to financial variables among farms with different ownership characteristics. These differences imply that the internal structure of the Czech cooperative and corporate farms will be developing in the direction of a decreasing number of owners and an increasing ownership concentration.

Drivers of Agricultural Physical Capital Development: Theoretical Framework and Hypotheses. Factor Markets Working Paper No. 18, February 2012

This paper aims to identify drivers of physical capital adjustments in agriculture. It begins with a review of some of the most important theories and modelling approaches regarding firms’ adjustments of physical capital, ranging from output-based models to more recent approaches that consider irreversibility and uncertainty. Thereafter, it is suggested that determinants of physical capital adjustments in agriculture can be divided into three main groups, namely drivers related to: i) expected (risk-adjusted) profit, ii) expected societal benefits and costs and iii) expected private nonpecuniary benefits and costs. The discussion that follows focuses on the determinants belonging to the first group and covers aspects related to product market conditions, technological conditions, financial conditions and the role of firm structure and organization. Furthermore, the role of subjective beliefs is emphasized. The main part of this paper is concerned with the demand side of the physical capital market and one section also briefly discusses some aspects related to supply of farm assets.

Determinants of Financial Capital Use: Review of theories and implications for rural businesses. Factor Markets Working Paper No. 19, February 2012

This paper presents a review of financial economics literature and offers a comprehensive discussion and systematisation of determinants of financial capital use. In congruence with modern financial literature, it is acknowledged here that real and financial capital decisions are interdependent. While the fundamental role of the (unconstrained) demand for real capital in the demand for finance is acknowledged, the deliverable focuses on three complementary categories of the determinants of financial capital use: i) capital market imperfections; ii) factors mitigating these imperfections or their impacts; and iii) firm- and sector-related factors, which alter the severity of financial constraints and their effects. To address the question of the optimal choice of financial instruments, theories of firm capital structure are reviewed. The deliverable concludes with theory-derived implications for agricultural and non-agricultural rural business’ finance.

Key Issues in Agricultural Labour Markets: A Review of Major Studies and Project Reports on Agriculture and Rural Labour Markets. Factor Markets Working Paper No. 20, February 2012

This paper provides a synthesis of the empirical literature on the key issues in agricultural and rural labour markets since 1960s, drawing mainly upon studies from the United States and the European Union, but also including relevant material from developing countries. The contribution of this meta-analysis lies in its unique structure as it covers the main research questions which have been addressed in the literature and includes the most cited papers from the American Journal of Agricultural Economics, Journal of Agricultural Economics, European Review of Agricultural Economics, Agricultural Economics as well as other reports and EU funded projects. Each research question is accompanied by tabular summaries which classify the individual studies according to the methodology and the variables employed. The heterogeneous conditions across countries, the different research questions and methodologies, and the type of data employed, have sometimes led to conflicting results. Nonetheless, by comparing the results it is possible to assess the significance and the direction of the determinants of rural labour allocation and its adjustments, and thus contribute to a better understanding on the functioning of rural labour markets. Lastly, by recognising the importance of the institutional framework, the paper provides useful policy insights.

Commonalities and Differences in Labour Market Developments and Constraints in Different EU Regions. Factor Markets Working Paper No. 22, February 2012

This paper provides a detailed overview of the differences across EU member states’ labour markets, through the extensive use of descriptive statistics. The objective is two-fold: firstly, it identifies the commonalities and differences in rural labour markets across EU regions and their developments, with special regard to agriculture, and secondly it emphasises the constraints that may hinder the efficient functioning of labour markets. Therefore, the paper starts with a description of the main indicators in the general labour market theory, such as the structure of the population in terms of age and gender distribution, unemployment and activity rates, employment levels, quality of human capital, migration patterns, and so forth. Secondly, we focus on the differences among rural and urban areas to then look closely at the agricultural sector. The institutional framework in which labour market institutions operate is also included. Lastly, as an attempt to summarise the analysis and to classify the EU member states according to certain rural and specific agricultural indicators, cluster analysis is also employed. Policy implications include investment in human capital and vocational training, support to young farmers, promoting economic diversification and upgrading infrastructure, with special regard to the new member states and to the Southern parts of Europe.

Does the Common Agricultural Policy Reduce Farm Labour Migration? Panel data analysis across EU regions. Factor Markets Working Paper No. 28, July 2012

This paper deals with the determinants of labour out-migration from agriculture across 149 EU regions over the 1990–2008 period. The central aim is to shed light on the role played by payments from the common agricultural policy (CAP) on this important adjustment process. Using static and dynamic panel data estimators, we show that standard neoclassical drivers, like relative income and the relative labour share, represent significant determinants of the intersectoral migration of agricultural labour. Overall, CAP payments contributed significantly to job creation in agriculture, although the magnitude of the economic effect was rather moderate. We also find that pillar I subsidies exerted an effect approximately two times greater than that of pillar II payments.

A Spatial Analysis of Agricultural Land Prices in Bavaria. Factor Markets Working Document No. 50, June 2013

This paper empirically analyses a dataset of more than 7,300 agricultural land sales transactions from 2001 and 2007 to identify the factors influencing agricultural land prices in Bavaria. We use a general spatial model, which combines a spatial lag and a spatial error model, and in addition account for endogeneity introduced by the spatially lagged dependent variable as well as other explanatory variables. Our findings confirm the strong influence of agricultural factors such as land productivity, of variables describing the regional land market structure, and of non-agricultural factors such as urban pressure on agricultural land prices. Moreover, the involvement of public authorities as a seller or buyer increases sales prices in Bavaria. We find a significant capitalisation of government support payments into agricultural land, where a decrease of direct payments by 1% would decrease land prices in 2007 and 2001 by 0.27% and 0.06%, respectively. In addition, we confirm strong spatial relationships in our dataset. Neglecting this leads to biased estimates, especially if aggregated data is used. We find that the price of a specific plot increases by 0.24% when sales prices in surrounding areas increase by 1%.

Cdk1 Restrains NHEJ through Phosphorylation of XRCC4-like Factor Xlf1

Eukaryotic cells use two principal mechanisms for repairing DNA double-strand breaks (DSBs): homologous recombination (HR) and nonhomologous end-joining (NHEJ). DSB repair pathway choice is strongly regulated during the cell cycle. Cyclin-dependent kinase 1 (Cdk1) activates HR by phosphorylation of key recombination factors. However, a mechanism for regulating the NHEJ pathway has not been established. Here, we report that Xlf1, a fission yeast XLF ortholog, is a key regulator of NHEJ activity in the cell cycle. We show that Cdk1 phosphorylates residues in the C terminus of Xlf1 over the course of the cell cycle. Mutation of these residues leads to the loss of Cdk1 phosphorylation, resulting in elevated levels of NHEJ repair in vivo. Together, these data establish that Xlf1 phosphorylation by Cdc2(Cdk1) provides a molecular mechanism for downregulation of NHEJ in fission yeast and indicates that XLF is a key regulator of end-joining processes in eukaryotic organisms.

Characterization of the Structure and Dynamics of Biomimetic Peptides by Solid-State NMR

Thesis (Ph.D.)--University of Washington, 2016-05

Modulation of Translation Efficiency in S. cerevisiae by Codon Pairs and mRNA Structure

Thesis (Ph.D.)--University of Washington, 2016-06