A note on the solutions of the Ginsparg-Wilson relation

The role of R in the solutions of the Ginsparg-Wilson relation is discussed.Comment: LaTeX, 12 pages, 4 figures, Equation (11) has been symmetrized to satisfy the hermiticity conditio

A construction of chiral fermion action

According to the necessary requirements for a chirally symmetric Dirac operator, we present a systematic construction of such operators. We formulate a criterion for the hermitian operator which enters the construction such that the doubled modes are decoupled even at finite lattice spacing.Comment: 6 page

Seismic Vulnerability and Risk Assessment of Historic Constructions: The Case of Masonry and Adobe Churches in Italy and Chile

Nowadays, disasters in seismic-prone areas such as Italy and Chile, continue to cause dramatic human and economic consequences and affecting, among others, very ancient and historical churches, due to their high seismic vulnerability and probably due to the lack of risk management plans for the conservation of cultural property. This paper focuses on rapid seismic risk assessment by applying two simplified methods, based on expert judgement and observed damage, in old masonry churches, which aim to identify the most vulnerable elements and correlated threats that would act as site effects under the seismic action, for establishing intervention priority lists and for planning preventive conservation projects. The case studies are: the church of Sant’Agostino, built in stone masonry and located in Matera, an area with moderate seismicity in southern Italy; the church of San Francisco de Chiu Chiu, built in adobe and located in Calama, an area with average seismicity in the Andean northern Chile; and the church of San Francisco Barón, built in adobe and brick masonry, and located in Valparaíso, an area with high seismicity on the central coast of Chile

The Index and Axial Anomaly of a lattice Dirac operator

A remarkable feature of a lattice Dirac operator is discussed. Unlike the Dirac operator for massless fermions in the continuum, this Ginsparg-Wilson lattice Dirac operator does not possess topological zero modes for any topologically-nontrivial background gauge fields, even though it is exponentially-local, doublers-free, and reproduces correct axial anomaly for topologically-trivial gauge configurations.Comment: 3 pages, LaTex, Lattice2001(chiral

The Index of a Ginsparg-Wilson Dirac operator

A novel feature of a Ginsparg-Wilson lattice Dirac operator is discussed. Unlike the Dirac operator for massless fermions in the continuum, this lattice Dirac operator does not possess topological zero modes for any topologically-nontrivial background gauge fields, even though it is exponentially-local, doublers-free, and reproduces correct axial anomaly for topologically-trivial gauge configurations.Comment: 8 pages, minor changes, the version to appear in Phys. Lett.

Variations in propagation delay times for line ten (TV) based time transfers

Variation in the propagation delay for a 30 km TV (Line Ten) radio link was evaluated for a series of 30 independent measurements. Time marks from TV Channel 5 WTTG in Washington, D.C. were simultaneously measured at the Johns Hopkins University Applied Physics Laboratory and at the United States Naval Observatory against each stations' local cesium standard clocks. Differences in the stations' cesium clocks were determined by portable cesium clock transfers. Thirty independent timing determinations were made. The root mean square deviation in the propagation delay calculated from the timing determinations was 11 ns. The variations seen in the propagation delays are believed to be caused by environmental factors and by errors in the portable clock timing measurements. In correlating the propagation delay variations with local weather conditions, only a moderate dependence on air temperature and absolute humidity was found

Modelling the growth of Salmonella spp. and Escherichia coli O157 on lettuce

This study aimed to model the growth of Salmonella and Escherichia coli O157 on lettuce at different temperatures. Microorganisms were inoculated separately on lettuce and stored at 5, 10, 25, and 37°C. Growth curves were built by fitting the data to the Baranyi’s DMFit model and Ratkowsky equation was used as secondary model. The models were able to assess the growth of both microorganisms and data showed that bacteria did not growth for 24 hours at 10°C, what can be a suitable temperature for lettuce distribution on food services. However, prolonged periods demonstrated growth at every temperatures examined