The influence of cardiac frequency on the hemodynamic consequences of mitral stenosis (author's transl)

In eleven patients with isolated mitral stenosis and regular sinus rhythm a right cardiac catheterization was performed and the wedged pulmonary capillary pressure recorded at rest and during electrical pacing of the right atrium at successive frequencies of 100, 120, 140, and, occasionally, 160 and 180 beats/min, while cardiac output was estimated by the Fick's principle. In all cases a significant elevation of pulmonary capillary pressure with a simultaneous reduction in cardiac output was obtained. The rise of wedged pulmonary pressure was proportional to the increment in cardiac frequency and related also to the calculated area of the mitral valve. The influence of active atrial contraction upon pulmonary pressure and cardiac output is discussed and comparisons with other studies are made. Emphasis is made on the value of atrial pacing as a diagnostic method in mitral stenosis, especially in cases in whom classical effort manoeuvres can not be applied or are insufficient to rise cardiac frequency.     

Dosimetric assessment from 212Pb inhalation at a thorium purification plant

At the Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, Brazil, there is a facility (thorium purification plant) where materials with high thorium concentrations are manipulated. In order to estimate afterwards the lung cancer risk for the workers, the thoron daughter (212Pb) levels were assessed and the committed effective and lung committed equivalent doses for workers in place. A total of 28 air filter samples were measured by total alpha counting through the modified Kusnetz method, to determine the 212Pb concentraion. The committed effective dose and lung committed equivalent dose due to 212Pb inhalation were derived from compartmental analysis following the ICRP 66 lung compartmental model, and ICRP 67 lead metabolic model.     

Three-component competitive adsorption model for flow-through PAC systems. 1. Model development and verification with a PAC/membrane system

Natural organic matter (NOM) interferes with the adsorption of trace organic compounds on porous adsorbents such as powdered activated carbon (PAC) by pore blockage and direct competition for adsorption sites. The competitive effect of NOM in flow-through systems in which the retention time of the PAC is greater than the hydraulic retention time of the system can be magnified because NOM from the influent water can continue to adsorb on the PAC retained in the system. As a result, the adsorption capacity and the diffusion coefficient of trace compounds can decrease as NOM from the influent water accumulates. In this study, a dynamic three-component adsorption model was developed to quantitatively describe the removal of a trace compound from water in flow-through PAC processes. The system was simplified by using p-dichlorobenzene (p-DCB) to represent the NOM fraction that competes directly with the target trace organic atrazine for adsorption sites and by using poly(styrene sulfonate) (PSS-1.8k) to represent large, pore-blocking NOM. The model was based on the homogeneous surface diffusion assumption with the adsorption capacity of atrazine being gradually adjusted using a simplified version of the ideal adsorbed solution theory model developed in this study. The surface diffusion coefficients of atrazine and p-DCB were modeled as a function of the surface concentration of the pore-blocking compound, PSS-1.8k. The model was verified experimentally with a PAC/microfiltration (MF) system. The use of single-solute adsorption parameters obtained from batch isotherm and kinetic tests resulted in good model predictions for the adsorption of atrazine and the two model compounds under operating conditions typical of PAC/MF systems. The model will be applied to study various operating conditions and other system parameters of PAC/membrane systems in part 2 of this study.     

Permeation of naproxen from saturated solutions and commercial formulations through synthetic membranes

The release of naproxen through synthetic membranes, mounted in modified Franz-type diffusion cells, was evaluated, either from saturated solutions or from commercially available topical formulations containing 10% naproxen. The results obtained showed that the porous type synthetic membranes chosen (cellulose acetate and polyethersulphone) can be used for assessing product performance in quality control procedures. The formulations interacted with the solid membranes (silicone and EVA) to change their diffusional characteristics. However, transfer in the membrane, and not the formulation was rate controlling. These membranes could not therefore be used in assessing product release performance for quality control.     

Valuing credit default swap in a non-homogeneous semi-Markovian rating based model

In this paper, we use a discrete time non-homogeneous semi-Markov model for the rating evolution of the credit quality of a firm C (see D’Amico, Janssen, and Manca Proceedings of the II international workshop in applied probablity, 2004a) and we determine the credit default swap spread for a contract between two parties, A and B that, respectively, sell and buy a protection about the failure of the firm C. We work both in the case of deterministic and stochastic recovery rate. We also highlight the link between credit risk and reliability theory.     

Towards useful and usable interaction design tools: CanonSketch

Despite all the effort dedicated to bringing better User-Centered Design (UCD) tools to market, current studies show that the industry is still dominated by tools that do not support the activities and workstyles of designers. Also, there is a growing need for interaction design tools aimed at software engineers, a problem related to bringing usability into the software engineering processes.

We propose a new workstyle model that can be effectively used to envision, design and evaluate a new generation of innovative interaction and software design tools, aimed at integrating usability and software engineering.

We illustrate the effectiveness of our model by describing a new tool, called CanonSketch, that was built in order to support UCD in terms of the dimensions in our workstyle model. We also describe an evaluation study aimed at contrasting paper prototyping with our tool as well as the level of workstyle support.     

What predicts psychological resilience after disaster? The role of demographics, resources, and life stress.

A growing body of evidence suggests that most adults exposed to potentially traumatic events are resilient. However, research on the factors that may promote or deter adult resilience has been limited. This study examined patterns of association between resilience and various sociocontextual factors. The authors used data from a random-digit-dial phone survey (N = 2,752) conducted in the New York City area after the September 11, 2001, terrorist attack. Resilience was defined as having 1 or 0 posttraumatic stress disorder symptoms and as being associated with low levels of depression and substance use. Multivariate analyses indicated that the prevalence of resilience was uniquely predicted by participant gender, age, race/ethnicity, education, level of trauma exposure, income change, social support, frequency of chronic disease, and recent and past life stressors. Implications for future research and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cumulative impact assessment on air quality from multiple open pit mines

Both open pit mine and smelter projects can have significant impacts on a variety of environmental resources. Among these, air quality of the surroundings is a key issue. Additionally, the environmental assessment of projects demands integrated approach taking in account all pollution sources. Therefore, specific focus has been put on the methodology for assessing impacts on air quality. This paper proposes an integrated index of environmental impact aiming to quantify the air quality impact of industrial operations around an urban area, in case of scarcity of in situ acquired data. This proposed pollution index is demonstrated by a case study conducted in the municipality of Congonhas, Brazil, in which contributions of five open pit mines and two smelters were studied. To achieve the pollution index, the wind rose and distances from the centroids of effective areas to the urban nucleus itself were considered, taking into account the wind projection areas from windward impacting sources on the leeward impacted urban site. The proposed index also includes the squared wind speed (proportional to the kinetic energy transferred in uplifting dust from ground surface). The method proposed is considered suitable for impact assignment for each one of the air pollution sources in the neighborhood of studied area. Some fluid dynamic aspects of airborne particulate matter are also studied by proposing a new equation for threshold saltation speed.     

A systematic review on the functional testing of semantic web services

Semantic web services are gaining more attention as an important element of the emerging semantic web. Therefore, testing semantic web services is becoming a key concern as an essential quality assurance measure. The objective of this systematic literature review is to summarize the current state of the art of functional testing of semantic web services by providing answers to a set of research questions. The review follows a predefined procedure that involves automatically searching 5 well-known digital libraries. After applying the selection criteria to the results, a total of 34 studies were identified as relevant. Required information was extracted from the studies and summarized. Our systematic literature review identified some approaches available for deriving test cases from the specifications of semantic web services. However, many of the approaches are either not validated or the validation done lacks credibility. We believe that a substantial amount of work remains to be done to improve the current state of research in the area of testing semantic web services.