The Connes-Lott program on the sphere

We describe the classical Schwinger model as a study of the projective modules over the algebra of complex-valued functions on the sphere. On these modules, classified by $\pi_2(S^2)$, we construct hermitian connections with values in the universal differential envelope which leads us to the Schwinger model on the sphere. The Connes-Lott program is then applied using the Hilbert space of complexified inhomogeneous forms with its Atiyah-Kaehler structure. It splits in two minimal left ideals of the Clifford algebra preserved by the Dirac-Kaehler operator D=i(d-delta). The induced representation of the universal differential envelope, in order to recover its differential structure, is divided by the unwanted differential ideal and the obtained quotient is the usual complexified de Rham exterior algebra over the sphere with Clifford action on the "spinors" of the Hilbert space. The subsequent steps of the Connes-Lott program allow to define a matter action, and the field action is obtained using the Dixmier trace which reduces to the integral of the curvature squared.Comment: 34 pages, Latex, submitted for publicatio

Connes-Lott model building on the two-sphere

In this work we examine generalized Connes-Lott models on the two-sphere. The Hilbert space of the continuum spectral triple is taken as the space of sections of a twisted spinor bundle, allowing for nontrivial topological structure (magnetic monopoles). The finitely generated projective module over the full algebra is also taken as topologically non-trivial, which is possible over $S^2$. We also construct a real spectral triple enlarging this Hilbert space to include "particle" and "anti-particle" fields.Comment: 57 pages, LATE

Age and quality of in-hospital care of patients with heart failure

Background: Elderly patients may be at risk of suboptimal care. Thus, the relationship between age and quality of care for patients hospitalized for heart failure was examined. Methods: A cross-sectional study based on retrospective chart review was performed among a random sample of patients hospitalized between 1996 and 1998 in the general internal medicine wards, with a principal diagnosis of congestive heart failure, and discharged alive. Explicit criteria of quality of care, grouped into three scores, were used: admission work-up (admission score); evaluation and treatment during the stay (evaluation and treatment score); and readiness for discharge (discharge score). The associations between age and quality of care scores were analysed using linear regression models. Results: Charts of 371 patients were reviewed. Mean age was 75.7 (±11.1) years and 52% were men. There was no relationship between age and admission or readiness for discharge scores. The evaluation and treatment score decreased with age: compared with patients less than 70 years old, the score was lower by −2.6% (95% CI: −7.1 to 1.9) for patients aged 70 to 79, by −8.7% (95% CI: −13.0 to −4.3) for patients aged 80 to 89, and by −19.0% (95% CI: −26.6 to −11.5) for patients aged 90 and over. After adjustment for possible confounders, this relationship was not significantly modified. Conclusions: In patients hospitalized for congestive heart failure, older age was not associated with lower quality of care scores except for evaluation and treatment. Whether this is detrimental to elderly patients remains to be evaluate

Non-commutative Quantum Mechanics in Three Dimensions and Rotational Symmetry

We generalize the formulation of non-commutative quantum mechanics to three dimensional non-commutative space. Particular attention is paid to the identification of the quantum Hilbert space in which the physical states of the system are to be represented, the construction of the representation of the rotation group on this space, the deformation of the Leibnitz rule accompanying this representation and the implied necessity of deforming the co-product to restore the rotation symmetry automorphism. This also implies the breaking of rotational invariance on the level of the Schroedinger action and equation as well as the Hamiltonian, even for rotational invariant potentials. For rotational invariant potentials the symmetry breaking results purely from the deformation in the sense that the commutator of the Hamiltonian and angular momentum is proportional to the deformation.Comment: 21 page

A Fully Bidirectional Optical Network With Latency Monitoring Capability for the Distribution of Timing-Trigger and Control Signals in High-Energy Physics Experiments

The present paper discusses recent advances on a Passive Optical Network inspired Timing-Trigger and Control scheme for the future upgrade of the TTC system installed in the LHC experiments' and more specifically the currently known as TTCex to TTCrx link. The timing PON is implemented with commercially available FPGAs and 1-Gigabit Ethernet PON transceivers and provides a fixed latency gigabit downlink that can carry level-1 trigger accept decisions and commands as well as an upstream link for feedback from the front-end electronics

FPGA-based Bit-Error-Rate Tester for SEU-hardened Optical Links

The next generation of optical links for future High-Energy Physics experiments will require components qualified for use in radiation-hard environments. To cope with radiation induced single-event upsets, the physical layer protocol will include Forward Error Correction (FEC). Bit-Error-Rate (BER) testing is a widely used method to characterize digital transmission systems. In order to measure the BER with and without the proposed FEC, simultaneously on several devices, a multi-channel BER tester has been developed. This paper describes the architecture of the tester, its implementation in a Xilinx Virtex-5 FPGA device and discusses the experimental results

Passive Optical Networks for the Distribution of Timed Signals in Particle Physics Experiments

A passive optical network for timing distribution applications based on FPGAs has been successfully demonstrated. Deterministic latency was achieved in the critical downstream direction where triggers are distributed while a burst mode receiver was successfully implemented in the upstream direction. Finally, a simple and efficient protocol was introduced for the communication between the OLT and the ONUs in the network that maximizes bandwidth utilization

Evaluation of produced water toxicity from an oil maritime terminal through Skeletonema costatum toxicity tests

The liquid effluent from an oil maritime terminal, with produced water as the main component, had its toxicity evaluated through toxicity tests with the diatom Skeletonema costatum. Two previously treated effluent samples (effluents A and B), were provided by PETROBRAS for the experiments. Both samples presented high salinity (67 for effluent A and 62 for effluent B) and low pH values (6.2), whereas total sulphide, phenol and nutrient content, dissolved/dispersed petroleum hydrocarbon concentration, BOD and COD values were quite different from each other. During the toxicity experiment, three replicate flasks with samples for each treatment were exposed to a light radiation of 266µE m² S-1 and maintained under a 10 h/14 h lightldark cycle, at a temperature of 24 :t 2ºC. The EC50 values could not be accurately estimated for effluent A: 60 h and 132 h after starting the experiment they were below 3% and between 3-6% effluent concentration, respectively. Synergistic effects between effluent toxicity and salinity on the growth of S. costatum were detected. The effluent B showed higher toxicity: the EC5O values were 0.17% and 0.40% of effluent concentrations, after 48 h and 96 h, respectively. These results evidenced the deleterious effects of residual organic compounds contained in the aqueous effluents from the oil terminal under the present pretreatment on S. costatum. In the light of the present data, the direct disposal ofthese effluents into São Sebastião Channel waters might be very hazardous to its indigenous biota.A toxicidade do efluente líquido do "Dutos e Terminais Centro-Oeste São Paulo" (DTCS) terminal marítimo de petróleo da PETROBRAS, em São Sebastião (SP, Brasil), cujo principal componente é a água de produção, foi avaliada através de testes de toxicidade com a diatomácea Skeletonema costatum. Amostras de dois efluentes (A e B), previamente tratados pela PETROBRAS, foram utilizadas nos experimentos. As duas amostras apresentaram alta salinidade (A=67; B=62) e baixo valor de pH (6,2), enquanto que as suas concentrações de sulfetos, fenóis e hidrocarbonetos de petróleo dissolvidos/dispersos, bem como os seus valores de DBO e DQO, foram bastante distintos. Nos experimentos de toxicidade, os frascos experimentais, em triplicata, para cada tratamento foram expostos à radiação luminosa fluorescente de 266 µm² S-1 e mantidas em um ciclo luz/escuro de 10 h/14 h, a uma temperatura de 24 :t 2ºC. Os valores de CE50 não puderam ser determinados com precisão para o efluente A: após 60 h e 132 h do início dos experimentos esses valores estavam abaixo de 3% e entre 3-6% da concentração de efluente, respectivamente. Foi observado sinergismo entre a toxicidade e a salinidade do efluente sobre o crescimento de S. costatum. O efluente B apresentou uma toxicidade mais elevada: os valores de CEso foram 0,17% e 0,40% da concentração do efluente, após 48 h e 96 h, respectivamente. Estes resultados evidenciaram claramente os efeitos deletérios dos compostos orgânicos residuais contidos no efluente líquido do DTCS, sobre S. costatum. Pode-se concluir que a disposição do efluente nas águas do canal de São Sebastião poderá ser prejudicial à biota local