A new functional calculus for non-commuting operators

In this paper we use the notion of slice monogenic functions \cite{slicecss} to define a new functional calculus for an $n$-tuple $T$ of not necessarily commuting operators. This calculus is different from the one discussed in \cite{jefferies} and it allows the explicit construction of the eigenvalue equation for the $n$-tuple $T$ based on a new notion of spectrum for $T$. Our functional calculus is consistent with the Riesz-Dunford calculus in the case of a single operator.Comment: to appear in Journal of Functional Analysi

Computer programs calculate potential and charge distributions in a plasma

Computer program determines the potential and charge distributions between two electrodes in a plasma. Solutions of the Vlasov equations for plane, cylindrical, and spherical geometries are determined and density distributions are found for each of these configurations over a range of conditions

The role of copper money within the dynamics of sovereign debt and the perception of unsound fiat money in 17th- century Castile

The aim of the following paragraphs is to assess the role of fiat copper coins within the cycle of negotiations and approvals concerning sovereign debt in Castile during the first 3 decades of the 17th- Century. The perception of unsound fiat money will be studied using primary sources. The attitudes of contemporaries towards the transformation of coins from quasi- commodity money into unsound fiat money will be featured within the context of Castile's legal and political framework, highlighting alternatives to a devaluation and suggestions to introduce types of currency other than fiat money

Selecting SUDS in the Valencia Region of Spain

This paper reports on a study of the implementation of sustainable urban drainage systems (SUDS) in two Spanish towns (Xàtiva and Benaguasil) as part of the EU LIFE+ Project AQUAVAL, which has been conceived to introduce examples of sustainable drainage to the Valencia Region of Spain. Six sites in a range of common urban spaces and land uses are selected and appropriate SUDS techniques proposed by means of a decision-support process. This primarily consisted of the systematic application of key selection criteria through matrices and scores, followed by a brief sustainability analysis. Stakeholders’ preferences and opinions as well as educational and social opportunities are highly considered throughout the process. General monitoring requirements and major limitations in using the methodology are outlined, stressing the need for improvement of four main aspects: local data regarding SUDS performance, detail of the sustainability analysis, support through comprehensive modelling tools, and level of stakeholder engagement. The importance of creating showcases for SUDS in Mediterranean Regions, thus adapting key selection criteria as to foster sustainable drainage understanding and expertise is highlighted

Silver production in 17th- century Spanish America: a preliminary analysis of its volatility, trajectory and possible effects on the Castilian monetary system

This paper presents a preliminary analysis of volatility in Peruvian and Mexican silver production series throughout the 17th-century, based on ARCH/GARCH models. Through a comparison of volatility patterns in the two viceroyalties, hypotheses on investor behaviour will be put forward and compared to theories on the relationship between risk and the development of merchant networks. Trends of silver production will be compared to trends of exchange rate series registered in Seville, exploring the possibility of a link between exchange rates in Seville and metal production in either viceroyalties

Selective adoption of mining and minting technological innovations in Habsburg colonial Mexico: Centralist policy or exchange rate management strategy?

Significant technological innovations in minting and mining emerged between the 16th and 17th centuries: improved technologies set new standards, which enhanced efficiency in both sectors. The reception of such innovations in Habsburg colonial Mexico was selective, however. Whilst most innovations in the mining sector were adopted and even further developed, minting activities remained centralised in the capital, Mexico City, and in accordance with medieval procedures. Although the first coin mill was adopted in Spain and installed in Segovia as early as 1583, it was only in 1732 that such device arrived in the Mexican capital, as part of the economic and political reforms carried out by Phillip V of Bourbon. Minting in Habsburg colonial Mexico, as far as technology is concerned, remained medieval throughout. An analysis of the underlying reasons for this disparity in the embracement of technological change in the two industries will be carried out. Special focus will be placed on the characteristics of money and silver demand in different mining areas as well as on the geographical, political, social and economic factors which may have contributed towards the non- adoption of technological change. Policy changes in respect to money supply carried out by the authorities and their effects will be analysed to reveal a possible rationale behind the exchange rate system between minted coins and bullion

Mining, market volatility and exchange rate management in early modern Mexico: Zacatecas and Guadalajara 1578-1669

This paper describes statistical evidence supporting the theory that early modern frontier mining towns in Mexico had more unstable economies than central agricultural towns. Series of sales tax revenues are used as a proxy for economic activity in the towns of Zacatecas and Guadalajara during the period of 1578-1669. A description of the analysis of variance will be presented, and differences in volatility patterns will be highlighted. Further, volatility will be placed within the context of the rate of discount paid by miners to exchange bullion for coins

Digital computer study of nuclear reactor thermal transients during startup of 60-kWe Brayton power conversion system

A digital computer study was made of reactor thermal transients during startup of the Brayton power conversion loop of a 60-kWe reactor Brayton power system. A startup procedure requiring the least Brayton system complication was tried first; this procedure caused violations of design limits on key reactor variables. Several modifications of this procedure were then found which caused no design limit violations. These modifications involved: (1) using a slower rate of increase in gas flow; (2) increasing the initial reactor power level to make the reactor respond faster; and (3) appropriate reactor control drum manipulation during the startup transient

Expression patterns of chondrocyte genes cloned by differential display in tibial dyschondroplasia

AbstractTibial dyschondroplasia (TD) appears to involve a failure of the growth plate chondrocytes within growing long bones to differentiate fully to the hypertrophic stage, resulting in a mass of prehypertrophic chondrocytes which form the avascular TD lesion. Many biochemical and molecular markers of chondrocyte hypertrophy are absent from the lesion, or show reduced expression, but the cause of the disorder remains to be identified. As differentiation to the hypertrophic state is impaired in TD, we hypothesised that chondrocyte genes that are differentially expressed in the growth plate should show altered expression in TD. Using differential display, four genes, B-cadherin, EF2, HT7 and Ex-FABP were cloned from chondrocytes stimulated to differentiate to the hypertrophic stage in vitro, and their differential expression confirmed in vivo. Using semi-quantitative RT-PCR, the expression patterns of these genes were compared in chondrocytes from normal and TD growth plates. Surprisingly, none of these genes showed the pattern of expression that might be expected in TD lesion chondrocytes, and two of them, B-cadherin and Ex-FABP, were upregulated in the lesion. This indicates that the TD phenotype does not merely reflect the absence of hypertrophic marker genes, but may be influenced by more complex developmental mechanisms/defects than previously thought