A Simple Empirical Calibration of Energy Dispersive X-Ray Analysis (EDXA) on the Cornea

Monitoring of the corneal electrolyte content is important for the study of chemical eye burns. This paper describes quantitative measurements on gelatin standards, corneas and a cornea homogenate with an energy dispersive X-ray analyzer (EDX) in the scanning electron microscope (SEM). Ten micrometers thick cryosections were freeze-dried and mounted on solid carbon supports. The applied quantification procedure was a local peak background analysis with a specifically designed computer program. Similar chemical and physical properties of gelatin, cornea homogenate, and cornea were proven by EDX-analysis and wet chemical analysis. Gelatin standards with known concentrations of different added salts showed linear correlations with a correlation coefficient higher than 0.95 for all considered elements. The local background generation on carbon supports was the same for gelatin standards and corneal tissue. The results demonstrate that quantitative EDX analysis of semi-thin samples, mounted on neutral carbon supports, can be reliably used for the assessment of the corneal mineral composition

Metabolomic analysis of human disease and its application to the eye

Metabolomics, the analysis of the metabolite profile in body fluids or tissues, is being applied to the analysis of a number of different diseases as well as being used in following responses to therapy. While genomics involves the study of gene expression and proteomics the expression of proteins, metabolomics investigates the consequences of the activity of these genes and proteins. There is good reason to think that metabolomics will find particular utility in the investigation of inflammation, given the multi-layered responses to infection and damage that are seen. This may be particularly relevant to eye disease, which may have tissue specific and systemic components. Metabolomic analysis can inform us about ocular or other body fluids and can therefore provide new information on pathways and processes involved in these responses. In this review, we explore the metabolic consequences of disease, in particular ocular conditions, and why the data may be usefully and uniquely assessed using the multiplexed analysis inherent in the metabolomic approach

Accuracy of the Aspartic Acid Racemization Technique in Age Estimation of Mammals and the Influence of Body Temperature

The aspartic acid racemization (AAR) technique has been applied for age estimation of humans and other mammals for more than four decades. In this study, eye lenses from 124 animals representing 25 mammalian species were collected and D/L ratios obtained using the AAR technique. The animals were either of known age or had the age estimated by other methods. The purpose of the study was to: a) estimate the accuracy of the AAR technique, and b) examine the effect of body temperature on racemization rates. Samples from four of the 25 species covered the range of ages that is needed to estimate species-specific racemization rates. The sample size from a single species of known age, the pygmy goat (Capra hircus, n = 35), was also large enough to investigate the accuracy of ages obtained using the AAR technique. The 35 goats were divided into three datasets: all goats (n = 35), goats >0.5 yrs old (n = 26) and goats >2 yrs old (n = 19). Leave-one-out analyses were performed on the three sets of data. Normalized root mean squared errors for the group of goats >0.5 yrs old were found to be the smallest. The higher variation in D/L measurements found for young goats 0.5 yrs old was for three age groups of the goats: 0.934 yrs for young goats 8 yrs (n = 4). Thus, the age of an adult or an old animal can be predicted with approximately 10% accuracy, whereas the age of a young animal is difficult to predict. A goat specific racemization rate, as a 2kAsp value, was estimated to 0.0107 ± 3.8 x 10-4 SE (n = 26). The 2kAsp values from 12 species, four estimated in this study and another eight published, were used to examine the effect of core body temperature on the rate of racemization. A positive relationship between AAR and temperature was found (r2 = 0.321) but results also suggest that other factors besides temperature are involved in the racemization process in living animals. Based on our results we emphasize that non-species-specific racemization rates should be used with care in AAR age estimation studies and that the period of postnatal growth of the eye lens be considered when estimating species-specific D/L0 values and ages of young individuals

Geography and Industry Meets Venture Capital

Do certain regions inherently enjoy an advantage in venture capital investment decisions? And how do industry characteristics affect venture capital activity? These questions fall under the reemerging study of economic geography, which suggests the importance of industrial location to economic decision making. Through the lens of economic geography, this paper examines the impact of industrial and regional characteristics on venture capital activities from 1996 to 2005. Analyzing venture capital data with nineteen regions and seventeen industries, this study affirms the significance of geography and industry to investment trends in venture capital.Venture Capital, Venture-Backed Public Companies, Economic Geography, Location, Biotechnology, Business Products and Services, Computers and Peripherals, Consumer Products and Services, Electronics and Instrumentation, Financial Services, Healthcare Services, Industrial and Energy, Information Technology Services, Media and Entertainment, Medical Devices and Equipment, Networking and Equipment, Retailing and Distribution, Semiconductors, Software, Telecommunications.

Corporate Tax Systems, Multinational Enterprises, and Economic Integration

Multinational firms are known to shift profits and countries are known to compete over shifty profits. Two major principles for corporate taxation are Separate Accounting (SA) and Formula Apportionment (FA). These two principles have very different qualities when it comes to preventing profit shifting and preserving national tax autonomy. Most OECD countries use SA. In this paper we show that a reduction in trade barriers lowers equilibrium corporate taxes under SA, but leads to higher taxes under FA. From a welfare point of view the choice of tax principle is shown to depend on the degree of economic integration.multinational enterprises, economic integration, trade costs, international tax competition, tax regimes

What we can and what we can't say about employment growth in specialised cities

There is an ongoing debate on whether certain sector structures enhance regional employment growth. Often, regional policies promote clusters and, hence, regional specialisation. It is commonly believed that clusters boost regional economic performance. However, in the present manuscript a simple model is introduced which suggests the reverse is true regarding employment growth. It is argued that specialised regions are prone to be affected stronger by sector-specific demand shocks than diversified ones and, therefore, show higher variances in employment growth rates. A test on the equality of variances in employment growth rates across two groups of specialised and diversified cities is conducted. It shows that, in Germany, variances are higher in the group of specialised cities. Thus, regional specialisation is more insecure than diversification with regard to stable employment growth rates. --

Wage Subsidy and Sector-Specific Unemployment: A New Economic Geography Approach

This paper uses a new economic geography approach to examine the effects of wage subsidy, which is undertake to bolster up the industrial development. This paper also highlights the effects of trade liberalization and international capital mobility. In particular, sector-specific unemployment is introduced in the monopolistically competitive sector of the home country.

Venture Capital Meets Industrial Sector and Location

This paper examines venture capital investment activity in the United States during the period 1995 to the first quarter 2009, taking into consideration both location and industry sector. The research question is whether industry and region are important factors in determining venture capital investment. Furthermore, the paper explores the effects of macroeconomic variables on investment activity. Consequently, the venture capital data are augmented by Gross Domestic Product (GDP), Federal Funds Rate, three, five and ten year interest rates. By examining long term trends, the effect of the current economic crisis on venture capital investment may be better understood.Venture Capital; Economic Geography; Location; Biotechnology; Business Products and Services; Computers and Peripherals; Consumer Products and Services; Electronics and Instrumentation; Financial Services; Healthcare Services; Industrial and Energy; Information Technology Services; Media and Entertainment; Medical Devices and Equipment; Networking and Equipment; Retailing and Distribution; Semiconductors; Software; Telecommunications

EU cohesion policy and the equity-efficiency trade-off - Adding dynamics to Martin's model

As a result of the combination of endogenous growth theory with the approach of the new economic geography (NEG), several models have been developed to explain spatial income inequality and to formulate possible policy strategies taking into account the equity-efficiency trade-off. The dynamics of this problem should be considered as fundamentally important for the enlargement of the EU, because with respect to the new Member States from Central and Eastern Europe (CEECs), EU cohesion policy is confronted with a double challenge: how can it contribute to attain higher national growth (and therefore convergence towards the EU average income per capita) and at the same time contribute to the decrease of regional disparities within the new Member States? This analysis is particularly appealing against the background of the alleged equity-efficiency trade-off that regional policies often suffer from. After the introduction, in the second part of this paper, some light is shed on this equity-efficiency trade-off in the framework of an overview surveying the theoretical literature on the issue. In the third part of the paper, a model presented by Philippe Martin (1999) is presented. Martin’s model combines the approaches of NEG and endogenous growth theory. In the fourth part, we develop a very simple dynamic version of the Martin model, followed by its formal analysis. We examine the effect of a monetary transfer to the poorer region, financed by the EU in the context of its cohesion policy interventions. In the fifth part, we derive some regional policy implications of the dynamised version of the Martin model. We find that there is a case for a “two step regional policy approach” in order to tackle the equity-efficiency trade-off challenge: this approach first aims to support the richer region and thus aggregate growth in the whole integrated area, and then to pursue an equity-oriented cohesion policy by fostering firm creation and innovation in the poorer region.

WHAT DOES GREATER ECONOMIC INTEGRATION MEAN FOR INTERREGIONAL INCOME INEQUALITY? AN ANALYSIS OF OECD COUNTRIES AND REGIONS

This paper provides an overview of the evolution of interregional income disparities among 304 regions from 27 OECD countries between 1995 and 2005. This sample of regions allows to compare interregional income inequality in different economic integration systems: the USA (used as an example of a political union), the European Economic and Monetary Union (EMU), the European Union (EU), and the North-American Free Trade Agreement (NAFTA). Overall, interregional income inequality is lower among US states and EMU regions than among EU regions and NAFTA regions. Thus, interregional income inequality seems to be negatively related to economic integration. However, income inequality has risen among US states, while it has been stable among OECD regions, and has even decreased among European regions. Moreover, rank-size scatterplots suggest that inequality is higher among low-income regions than among richer regions.REGIONAL INEQUALITY, ECONOMIC INTEGRATION, EUROPEAN UNION, EMU, NAFTA, ZIPF LAW