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An explicitly time-dependent (TD) approach to equation-of-motion (EOM) coupled-cluster theory with single and double excitations (CCSD) is implemented for simulating near-edge X-ray absorption fine structure in molecular systems. The TD-EOM-CCSD absorption line shape function is given by the Fourier transform of the CCSD dipole autocorrelation function. We represent this transform by its Padé approximant, which provides converged spectra in much shorter simulation times than are required by the Fourier form. The result is a powerful framework for the blackbox simulation of broadband absorption spectra. K-edge X-ray absorption spectra for carbon, nitrogen, and oxygen in several small molecules are obtained from the real part of the absorption line shape function and are compared with experiment. The computed and experimentally obtained spectra are in good agreement; the mean unsigned error in the predicted peak positions is only 1.2 eV. We also explore the spectral signatures of protonation in these molecules.

We report an explicitly time-dependent approach to the generation of linear absorption spectra for molecular systems within the framework of equation-of-motion (EOM) coupled-cluster (CC) theory. While most time-dependent CC approaches consider the perturbation and time-evolution of a CC wave function, the present work considers the time-evolution of a CC dipole function. The dipole function formalism introduces no approximations and requires the evolution of only one time-dependent quantity, either the left or right dipole function. This time-dependent framework can be used to compute linear absorption spectra for molecules with a high density of states over a broad spectral range, a case for which conventional frequency-domain computations may become impractical. We validate the approach by comparing absorption spectra for small molecules computed at EOM second-order approximate CC (CC2) and time-dependent EOM-CC2 (TD-EOM-CC2) levels of theory. TD-EOM-CC2 computations are also used to predict extreme ultraviolet absorption spectra for third-row ions that are in reasonable agreement with experiment.

We present a combined cavity quantum electrodynamics/ab initio electronic structure approach for simulating plasmon-molecule interactions in the time domain. The simple Jaynes-Cummings-type model Hamiltonian typically utilized in such simulations is replaced with one in which the molecular component of the coupled system is treated in a fully ab initio way, resulting in a computationally efficient description of general plasmon-molecule interactions. Mutual polarization effects are easily incorporated within a standard ground-state Hartree-Fock computation, and time-dependent simulations carry the same formal computational scaling as real-time time-dependent Hartree-Fock theory. As a proof of principle, we apply this generalized method to the emergence of a Fano-like resonance in coupled molecule-plasmon systems; this feature is quite sensitive to the nanoparticle-molecule separation and the orientation of the molecule relative to the polarization of the external electric field.

We present a parametrized coupled-pair functional, optimized to describe molecular interactions (PCPF-MI). The method has the same computational cost as singles and doubles configuration interaction, is size extensive, and yields energies that are stationary with respect to variations in all of its excitation coefficients. This last property facilitates the construction of density matrices and the evaluation of one- and two-electron properties. For the S22, HSG, S66, and A24 databases of van der Waals dimers, PCPF-MI computations yield interaction energies with mean unsigned errors of 0.326, 0.149, 0.214, and 0.044 kcal mol(-1), respectively, relative to benchmark computations. PCPF-MI interaction energies consistently improve upon those obtained from several other coupled-pair methods, including the averaged coupled-pair functional (ACPF), the coupled electron-pair approximation [CEPA(n), n = 0,1,3], and averaged quadratic coupled cluster (AQCC). Optimal parameters for spin-component-scaled (SCS) variants of each of these methods are also presented. SCS-CEPA(0), SCS-CEPA(1), SCS-ACPF, and SCS-PCPF-MI all perform similarly, with average errors for the four databases of roughly 0.1 kcal mol(-1). The PCPF-MI method, without additional SCS parametrization, has an average error of 0.192 kcal mol(-1) over the four databases and, when compared to the SCS-parametrized coupled-pair methods, has the added benefit that the energy is stationary with respect to variations in all its excitation coefficients.

This article analyzes a debate brought to the public arena by Jornal do Commercio newspaper in August and September 1899 involving two sanitation officials: Nuno de Andrade, Director-General of Public Health, and Jorge Pinto, Director of Hygiene and Public Welfare of the State of Rio de Janeiro. The issue in question was the measures taken by the federal government to prevent bubonic plague reaching Brazil from Porto, Portugal, where there was an epidemic. The theoretical framework for the analysis is Pierre Bourdieu's notion of field, and Bruno Latour's studies into scientific controversy.

In the present study, a flow injection system using dual mini-columns, SiO(2)/Al(2)O(3)/TiO(2) and silica gel functionalized with [3-(2-aminoethylamino)propyl] trimethoxysilane (SiO(2)/AAPTMS) for the sequential preconcentration of Cr(III) and Cr(VI), respectively, from water samples with FAAS detection was proposed. A two-level full factorial design (2(4)) and desirability function were employed for the optimization of variables related to the system performance. The detection limits of 0.66 and 0.27 μg L(-1) for Cr(III) and Cr(IV), respectively, were obtained under the optimized preconcentration conditions (flow rate of 7.0 mL min(-1)), pH 5.0, buffer concentration (acetate buffer) of 0.01 mol L(-1), and eluent (2.5 mol L(-1) HCl) flow rate of 5.0 mL min(-1). The other parameters including preconcentration factor (PF), consumptive index (CI), and concentration efficiency (CE) were found to be 17.62/32.98, 1.13/0.6 mL, and 6.2/11.54 min(-1) for Cr(III)/Cr(VI), respectively. The developed method was applied to the Cr(III) and Cr(VI) determination in water samples [tap, lake and mineral water, artificial saliva and parenteral solutions (physiological serum, water for injection, and glucose physiological solution)]. The method accuracy was checked by the analysis of standard reference materials (trace elements in water)., (Copyright © 2012 Elsevier B.V. All rights reserved.)

We evaluated the expression of the Fas receptor gene in Vero cells infected with the Lederle vaccine strain of canine distemper virus using RT-PCR. Vero cells were plated, and after being grown for 24 h in MEM with 5% FBS, 80-90% confluent monolayer cultures were infected with the virus. The cells were harvested at 3, 6, 9, and 15 h post-infection. Uninfected Vero cells were used as a control. Total RNA was isolated from Vero cells using 1 mL Trizol(®) LS, and RT was performed using 2 μg total RNA. Primer pairs for RT-PCR amplification for the canine distemper virus nucleocapsid gene, the S26 reference gene, and the Vero rFas gene were used to analyze expression in Vero cells. RT-PCR results revealed virus activity at 3, 6, 9, and 15 h in the virus-infected Vero cells. The S26 housekeeping gene was amplified in virus infected and control samples. However, expression of the cell death receptor Fas was detected in Vero cells only at 15 h post-infection. We suggest that the Lederle vaccine induces apoptosis by Fas receptor signaling, possibly through caspase-8 signaling rather than through mitochondrial signaling in the infected cells.

This article discusses the vaccination campaigns against poliomyelitis in Brazil. It examines issues that have shaped the politics of disease control at the interface with the history of science and technology with regard to the discovery of vaccines, the development of laboratory techniques for diagnosis and surveillance of new procedures, and history of public health policies in relation to decision making and implementation of control and eradication of disease. The aim is also to demonstrate that in addition to the technologies available, it was necessary some negotiation and political will to achieve the control and eradication of the disease in the country. The main sources used were scientific articles, oral testimonies, official documents and newspaper articles.

In October 1899, the bubonic plague arrived in Brazil through the port of Santos. A city of intensive port activity, Santos was the gateway for a plague epidemic that devastated several cities in Brazil in the early 20th century and prompted joint action by several states to fight it. More importantly, given the difficulties and delays in importing anti-plague serum from Europe, it led to the creation of the Butantan Institute in Sao Paulo (in 1899) and the Municipal Serotherapeutic Institute in Rio de Janeiro (in 1900), which developed and standardized anti-plague serum and vaccines according to the particular conditions of the country. Until then, public health efforts had been isolated and had not reached the whole country. Oswaldo Cruz, newly arrived after three years of specialization at the Pasteur Institute in Paris, worked with scientists Adolfo Lutz and Vital Brazil on identifying the plague in Santos. This article analyzes the arrival of the bubonic plague epidemic in the state of Sao Paulo and the public health measures taken to combat the disease and provide patient care in the early part of the 20th century. The primary sources for this analysis were the São Paulo newspapers, especially O Estado de Sao Paulo, and reports from the Ministry of Justice and the President of the State of Sao Paulo.

The article analyzes the scientific and political discussions and activities surrounding the problem of polio in Brazil during the twentieth century. It examines the issues that shaped disease control policy and led to the 1980 introduction of National Vaccination Days.