An agent-based approach to modelling driver route choice behaviour under the influence of real-time information

This paper presents an agent-based approach to modelling individual driver behaviour under the influence of real-time traffic information. The driver behaviour models developed in this study are based on a behavioural survey of drivers which was conducted on a congested commuting corridor in Brisbane, Australia. Commuters' responses to travel information were analysed and a number of discrete choice models were developed to determine the factors influencing drivers' behaviour and their propensity to change route and adjust travel patterns. Based on the results obtained from the behavioural survey, the agent behaviour parameters which define driver characteristics, knowledge and preferences were identified and their values determined. A case study implementing a simple agent-based route choice decision model within a microscopic traffic simulation tool is also presented. Driver-vehicle units (DVUs) were modelled as autonomous software components that can each be assigned a set of goals to achieve and a database of knowledge comprising certain beliefs, intentions and preferences concerning the driving task. Each DVU provided route choice decision-making capabilities, based on perception of its environment, that were similar to the described intentions of the driver it represented. The case study clearly demonstrated the feasibility of the approach and the potential to develop more complex driver behavioural dynamics based on the belief-desire-intention agent architecture. (C) 2002 Elsevier Science Ltd. All rights reserved.

Chitosan as a Bioadhesive Agent Between Porphyrins and Phospholipids in a Biomembrane Model

Porphyrins are currently used in photodynamic therapy as photosensitizers. In this paper we studied the interaction of two charged porphyrins, 5, 10, 15, 20-mesotetrakis(N-metyl-4-pyridyl) porphyrin, (TMPyP/chloride salt) cationic, and 5, 10, 15, 20-meso-tetrakis(sulfonatophenyl) porphyrin, (TPPS(4)/sodium salt) anionic, nanoassembled in phospholipid Langmuir monolayers and Langmuir-Blodgett films. Furthermore, we used chitosan to mediate the interaction between the porphyrins and the model membrane, aiming to understand the role of the polysaccharide in a molecular level. The effect of the interaction of the photosensitizers on the fluidity of the lipid monolayer was investigated by using dilatational surface elasticity. We also used photoluminescence (PL) spectroscopy to identify the porphyrins adsorbed in the phospholipid films. We observed an expansion of the monolayer promoted by the adsorption of the porphyrins into the lipid-air interface which was more pronounced in the case of TMPyP, as a consequence of a strong electrostatic interaction with the anionic monolayer. The chitosan promoted a higher adsorption of the porphyrins on the phospholipid monolayers and enabled the porphyrin to stay in its monomeric form (as confirmed by PL spectroscopy), thus demonstrating that chitosan can be pointed out as a potential photosensitizer delivery system in photodynamic therapy.

Characterization of the Biocompatible Magnetic Colloid on the Basis of Fe(3)O(4) Nanoparticles Coated with Dextran, Used as Contrast Agent in Magnetic Resonance Imaging

The magnetic resonance imaging contrast agent, the so-called Endorem (TM) colloidal suspension on the basis of superparamagnetic iron oxide nanoparticles (mean diameter of 5.5 nm) coated with dextran, were characterized on the basis of several measurement techniques to determine the parameters of their most important physical and chemical properties. It is assumed that each nanoparticle is consisted of Fe(3)O(4) monodomain and it was observed that its oxidation to gamma-Fe(2)O(3) occurs at 253.1 degrees C. The Mossbauer spectroscopy have shown a superparamagnetic behavior of the magnetic nanoparticles. The Magnetic Resonance results show an increase of the relaxation times T(1), T(2), and T(2)* with decreasing concentration of iron oxide nanoparticles. The relaxation effects of SPIONs contrast agents are influenced by their local concentration as well as the applied field strength and the environment in which these agents interact with surrounding protons. The proton relaxation rates presented a linear behavior with concentration. The measured values of thermooptic coefficient partial derivative n/partial derivative T, thermal conductivity K, optical birefringence Delta n(0), nonlinear refractive index n(2), nonlinear absorption beta` and third-order nonlinear susceptibility vertical bar chi((3))vertical bar are also reported.

Characterization of Superparamagnetic Iron Oxide Coated with Silicone Used as Contrast Agent for Magnetic Resonance Image for the Gastrointestinal Tract

The present work is a report of the characterization of superparamagnetic iron oxide nanoparticles coated with silicone used as a contrast agent in magnetic resonance imaging of the gastrointestinal tract. The hydrodynamic size of the contrast agent is 281.2 rim, where it was determined by transmission electron microscopy and a Fe(3)O(4) crystalline structure was identified by X-ray diffraction, also confirmed by Mossbauer Spectroscopy. The blocking temperature of 190 K was determined from magnetic measurements based on the Zero Field Cooled and Field Cooled methods. The hysteresis loops were measured at different temperatures below and above the blocking temperature. Ferromagnetic resonance analysis indicated the superparamagnetic nature of the nanoparticles and a strong temperature dependence of the peak-to-peak linewidth Delta H(pp), giromagnetic factor g, number of spins N(S) and relaxation time T(2) were observed. This behavior can be attributed to an increase in the superexchange interaction.

The generation of H-1-NMR-detectable mobile lipid in stimulated lymphocytes: Relationship ts cellular activation, the cell cycle, and phosphatidylcholine-specific phospholipase C

Mobile Lipids detected using H-1-NMR in stimulated lymphocytes were correlated with cell cycle phase, expression of the interleukin-2 receptor alpha and proliferation to assess the activation status of the lymphocytes. Mobile lipid levels, IL-2R alpha expression and proliferation increased after treatment with PMA and ionomycin. PMA or ionomycin stimulation alone induced increased IL-2R alpha expressiom but not proliferation, PMA- but not ionomycin-stimulation generated mobile lipid, Treatment with anti-CD3 antibody did not increase IL-2R alpha expression or proliferation but did generate increased amounts of mobile lipid, The cell cycle status of thymocytes treated with anti-CD3, PMA or ionomycin alone indicated an. accumulation of the cells in the G(1) phase of the cell cycle, The generation of mobile lipid was abrogated in anti-CD3 antibody-stimulated thymic lymphocytes but not in splenic lymphocytes, using a phosphatidylcholine-specific phospholipase C (PC-PLC) inhibitor which blocked cells in the G(1)/S phase of the cell cycle, This suggests that the H-1-NMR-detectable mobile Lipid may be generated in anti-CD3 antibody-stimulated thymic lymphocytes by the action of PC-PLC activity via the catabolism of PC, in the absence of classical signs of activation. (C) 1997 Academic Press.

Can Mobile Units Improve the Strategies for Cervical Cancer Prevention?

Cervical cancer is a serious public health problem in women in developing countries because of absence or ineffectiveness of screening programs. Several biases to access medical care and inequity of public health system in a continental country like Brazil limit the implementation of adequate programs to appropriately prevent the cervical cancer. Therefore, the aim of this study was to evaluate the results of applying the mobile unit (MU) for cervical cancer screening. From May 2003 to May 2004, a cervical cancer screening was offered to women aged 20-69 years, residing in 19 municipal districts of the Barretos county region, in Sao Paulo. Out of the 9,560 examination available, 2,964 (31%) women underwent screening. The medium distance traveled by the MU was 45 km. The medium time spent by women in the MU for completion of the questionnaire and doing the exam was 20 minutes. It was observed that 17.0% of women screened had never had the test or had not had it repeated within the last 3 years. The negative response was more common among women aged 20 to 29 years and 60 to 69 years and among women with less schooling and lower socio-economic income (P < 0.05). MU can significantly overcome the chronic deficiency of public health system accessibility offering opportunity to these women to participate in screening programs. Diagn. Cytopathol. 2010;38:727-730. (C) 2009 Wiley-Liss, Inc.

Program for Prostate Cancer Screening Using a Mobile Unit: Results From Brazil

OBJECTIVES To evaluate the initial results of a prostate cancer screening program using mobile units in Brazil. METHODS Since 2004, we have conducted a program of prostate cancer screening using mobile units across 231 municipalities from 6 Brazilian states. RESULTS A total of 17 571 men were evaluated by clinical history, digital rectal examination (DRE), and serum free and total prostate-specific antigen (PSA) levels. The recommendations for biopsy were a PSA level of >= 4.0 ng/mL, DRE findings suspicious for cancer, or a PSA level of 2.5-4.0 ng/mL with a percent-free PSA level <15%. The biopsy protocol included 12 biopsy cores from the peripheral zone, 2 from the transition zone, and additional sampling of suspicious areas. The cumulative cancer detection rate was 3.7%. The main indication for biopsy was a PSA level of >= 4.0 ng/mL (51.2%), with a positive predictive value (PPV) of 44.1%. Another 19.7% of biopsied men had suspicious DRE findings with a normal PSA level (PPV 23.5%). A percent-free PSA level of <15% in men with a PSA level of 2.5-4.0 ng/mL and normal DRE findings yielded a PPV of 31.1%. The PPV was greater (70.9%) for the 7.1% of men with both suspicious DRE findings and a PSA level of >4.0 ng/mL. Most cancers were Stage T1-T2 (93.4%), and the percentage of Gleason score of >= 7 was 32.5%. The proportion of insignificant cancers according to Epstein`s criteria was 13.5%. CONCLUSIONS A mobile prostate cancer screening unit enabled an underserved population to gain access to specialized care through the public healthcare system. The cancer detection rate in this population was similar to those from international studies. UROLOGY 76: 1052-1057, 2010. (C) 2010 Published by Elsevier Inc.

Treatment for low-risk gestational trophoblastic disease: Comparison of single-agent methotrexate, dactinomycin and combination regimens

Objectives. To compare the efficacy of three different standard chemotherapy regimens for low-risk gestational trophoblastic disease according to the FIGO staging system in a single-institute setting. Methods. From 1980 until 2002, we retrospectively reviewed 108 cases with low-risk persistent gestational trophoblastic disease who were treated with first-line chemotherapy. Patients were divided in three groups according to chemotherapy regimen: patients treated with methotrexate (MTX group; n=42), patients treated with dactinomycin (ACT group; n=42) and patients treated with methotrexate and dactinomycin in combination (MACT group; n=24). We compared the number of chemotherapy courses for achieving remission, the duration of treatment, the adverse side effects, the efficacy of the treatment and the need for performing a hysterectomy among the groups Results. The complete remission rates were 69%, 61.4% and 79.1% for methotrexate (MTX), dactinomycin (ACT) and the combination regimen (MACT) treated groups, respectively (p=0.7). The duration of the treatment and the number of chemotherapy courses were similar among the groups (p = 0.2 and p = 0.4, respectively). Adverse side effects rate was reported to be 62.5% in the MACT group, 28.6% in the MTX group and 19.1% in the ACT group (p=0.0003). Second-line chemotherapy was indicated for 30 patients. Hysterectomy was performed in 21 patients overall, and there was no difference among the groups (P=0.6). Conclusion. Our analysis indicates that single-agent chemotherapy regimens are as effective as combination chemotherapy for low-risk gestational trophoblastic disease. Dactinomycin is a less toxic drug and might offer the best cost-effective treatment option. Methotrexate must be considered as the regimen of choice for low resource areas because of the feasibility of its administration. (c) 2007 Elsevier Inc. All rights reserved.

Network structures of Bis-GMA/TEGDMA resins differ in DC, shrinkage-strain, hardness and optical properties as a function of reducing agent

Objectives. To evaluate the influence of different tertiary amines on degree of conversion (DC), shrinkage-strain, shrinkage-strain rate, Knoop microhardness, and color and transmittance stabilities of experimental resins containing BisGMA/TEGDMA (3: 1 wt), 0.25wt% camphorquinone, 1wt% amine (DMAEMA, CEMA, DMPT, DEPT or DABE). Different light-curing protocols were also evaluated. Methods. DC was evaluated with FTIR-ATR and shrinkage-strain with the bonded-disk method. Shrinkage-strain-rate data were obtained from numerical differentiation of shrinkage-strain data with respect to time. Color stability and transmittance were evaluated after different periods of artificial aging, according to ISO 7491: 2000. Results were evaluated with ANOVA, Tukey, and Dunnett`s T3 tests (alpha = 0.05). Results. Studied properties were influenced by amines. DC and shrinkage-strain were maximum at the sequence: CQ < DEPT < DMPT <= CEMA approximate to DABE < DMAEMA. Both DC and shrinkage were also influenced by the curing protocol, with positive correlations between DC and shrinkage-strain and DC and shrinkage-strain rate. Materials generally decreased in L* and increased in b*. The strong exception was the resin containing DMAEMA that did not show dark and yellow shifts. Color varied in the sequence: DMAEMA < DEPT < DMPT < CEMA < DABE. Transmittance varied in the sequence: DEPT approximate to DABE < DABE approximate to DMPT approximate to CEMA < DMPT approximate to CEMA approximate to DMAEMA, being more evident at the wavelength of 400 nm. No correlations between DC and optical properties were observed. Significance. The resin containing DMAEMA showed higher DC, shrinkage-strain, shrinkage-strain rate, and microhardness, in addition to better optical properties. (C) 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Sodium bicarbonate solution as an anti-erosive agent against simulated endogenous erosion

This study investigated whether sodium bicarbonate solution, applied on enamel previously exposed to a simulated intrinsic acid, can control dental erosion. Volunteers wore palatal devices containing enamel slabs, which were exposed twice daily extra-orally to hydrochloric acid (0.01 M, pH 2) for 2 min. Immediately afterwards, the palatal devices were re-inserted in the mouth and volunteers rinsed their oral cavity with a sodium bicarbonate solution or deionized water for 60 s. After the washout period, the palatal devices were refilled with a new set of specimens and participants were crossed over to receive the alternate rinse solution. The surface loss and surface microhardness (SMH) of specimens were assessed. The surface loss of eroded enamel rinsed with a sodium bicarbonate solution was significantly lower than the surface loss of eroded enamel rinsed with deionized water. There were no differences between treatments with sodium bicarbonate and deionized water for SMH measurements. Regardless of the solution used as an oral rinse, eroded enamel showed lower SMH than uneroded specimens. Rinsing with a sodium bicarbonate solution after simulated endogenous erosive challenge controlled enamel surface loss but did not alter the microhardness.