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The CDISC Standard for Exchange of Nonclinical Data (SEND) data standard has created new opportunities for collaborative development of open-source software solutions to facilitate cross-study analyses of toxicology study data. A public-private partnership between BioCelerate and the FDA/Center for Drug Evaluation and Research (CDER) was established in part to develop and publicize novel methods to facilitate cross-study analysis of SEND datasets. As part of this work in collaboration with the Pharmaceutical Users Software Exchange (PHUSE), an R package sendigR has been developed to enable users to construct a relational database from a collection of SEND datasets and then query that database to perform cross-study analyses. The sendigR package also includes an integrated Python package, xptcleaner, which can be used to harmonize the terminology used in SEND datasets by mapping to CDISC controlled terminologies. The sendigR R package is freely available on the comprehensive R Archive Network (CRAN) and at https://github.com/phuse-org/sendigR. An R Shiny web application was included in the R package to enable toxicologists with no coding experience to perform historical control analyses. Experienced R programmers will be able to integrate the package functions into their own custom scripts/packages and potentially contribute improvements to the functionality of sendigR. sendigR reference manual: https://phuse-org.github.io/sendigR/. sendigR R Shiny demo app: https://phuse-org.shinyapps.io/sendigR/.
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FIREBIRD-II is a National Science Foundation funded CubeSat mission designed to study the scale size and energy spectrum of relativistic electron microbursts. The mission consists of two identical 1.5 U CubeSats in a low earth polar orbit, each with two solid state detectors that differ only in the size of their geometric factors and fields of view. Having two spacecraft in close orbit allows the scale size of microbursts to be investigated through the intra-spacecraft separation when microbursts are observed simultaneously on each unit. Each detector returns high cadence (10 s of ms) measurements of the electron population from 200 keV to >1 MeV across six energy channels. The energy channels were selected to fill a gap in the observations of the Heavy Ion Large Telescope instrument on the Solar, Anomalous, and Magnetospheric Particle Explorer. FIREBIRD-II has been in orbit for 5 years and continues to return high quality data. After the first month in orbit, the spacecraft had separated beyond the expected scale size of microbursts, so the focus has shifted toward conjunctions with other magnetospheric missions. FIREBIRD-II has addressed all of its primary science objectives, and its long lifetime and focus on conjunctions has enabled additional science beyond the scope of the original mission. This paper presents a brief history of the FIREBIRD mission's science goals, followed by a description of the instrument and spacecraft. The data products are then discussed along with some caveats necessary for proper use of the data.
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To determine the potential of a non-invasive acoustic device (CADScor®System) to reclassify patients with intermediate pre-test probability (PTP) and clinically suspected stable coronary artery disease (CAD) into a low probability group thereby ruling out significant CAD. Audio recordings and clinical data from three studies were collected in a single database. In all studies, patients with a coronary CT angiography indicating CAD were referred to coronary angiography. Audio recordings of heart sounds were processed to construct a CAD-score. PTP was calculated using the updated Diamond-Forrester score and patients were classified according to the current ESC guidelines for stable CAD: low < 15%, intermediate 15-85% and high > 85% PTP. Intermediate PTP patients were re-classified to low probability if the CAD-score was ≤ 20. Of 2245 patients, 212 (9.4%) had significant CAD confirmed by coronary angiography ( ≥ 50% diameter stenosis). The average CAD-score was higher in patients with significant CAD (38.4 ± 13.9) compared to the remaining patients (25.1 ± 13.8; p < 0.001). The reclassification increased the proportion of low PTP patients from 13.6% to 41.8%, reducing the proportion of intermediate PTP patients from 83.4% to 55.2%. Before reclassification 7 (3.1%) low PTP patients had CAD, whereas post-reclassification this number increased to 28 (4.0%) (p = 0.52). The net reclassification index was 0.209. Utilization of a low-cost acoustic device in patients with intermediate PTP could potentially reduce the number of patients referred for further testing, without a significant increase in the false negative rate, and thus improve the cost-effectiveness for patients with suspected stable CAD.
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Enfermedad de la Arteria Coronaria/diagnóstico , Estenosis Coronaria/diagnóstico , Ruidos Cardíacos , Fonocardiografía , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/clasificación , Enfermedad de la Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria/clasificación , Estenosis Coronaria/economía , Estenosis Coronaria/fisiopatología , Ahorro de Costo , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Fonocardiografía/economía , Fonocardiografía/instrumentación , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
We describe a new data product combining the spin-averaged electron flux measurements from the Radiation Belt Storm Probes (RBSP) Energetic Particle Composition and Thermal Plasma (ECT) suite on the National Aeronautics and Space Administration's Van Allen Probes. We describe the methodology used to combine each of the data sets and produce a consistent set of spectra for September 2013 to the present. Three-minute-averaged flux spectra are provided spanning energies from 15 eV up to 20 MeV. This new data product provides additional utility to the ECT data and offers a consistent cross calibrated data set for researchers interested in examining the dynamics of the inner magnetosphere across a wide range of energies.
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In southern Norway, 22 acidified rivers supporting anadromous salmonids were mitigated with lime to improve water quality and restore fish populations. In 13 of these rivers, effects on Salmo trutta and Salmo salar densities were monitored over 10-12 years, grouped into age 0 and age ≥ 1 year fish. These rivers had a mean annual discharge of between 4·9 and 85·5 m3 s-1 , and six of them were regulated for hydro-power production. Salmo salar were lost in six of these rivers prior to liming, and highly reduced in the remaining seven rivers. Post-liming, S. salar became re-established in all six rivers with lost populations, and recovered in the seven other rivers. Salmo trutta occurred in all 13 study rivers prior to liming. Despite the improved water quality, both age 0 and age ≥ 1 year S. trutta densities decreased as S. salar density increased, with an average reduction of >50% after 10 years of liming. For age 0 year S. trutta this effect was less strong in rivers where S. salar were present prior to liming. In contrast, densities of S. trutta increased in unlimed streams above the anadromous stretches in two of the rivers following improved water quality due to natural recovery. Density increases of both age 0 and age ≥ 1 year S. salar showed a positive effect of river discharge. The results suggest that the decline in S. trutta density after liming is related to interspecific resource competition due to the recovery of S. salar. Thus, improved water quality through liming may not only sustain susceptible species, but can have a negative effect on species that are more tolerant prior to the treatment, such as S. trutta.
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Restauración y Remediación Ambiental , Ríos/química , Salmo salar/fisiología , Trucha/fisiología , Animales , Compuestos de Calcio , Conservación de los Recursos Naturales , Noruega , ÓxidosRESUMEN
INTRODUCTION: The Merck Adenovirus-5 Gag/Pol/Nef HIV-1 subtype-B vaccine evaluated in predominately subtype B epidemic regions (Step Study), while not preventing infection, exerted vaccine-induced immune pressure on HIV-1 breakthrough infections. Here we investigated if the same vaccine exerted immune pressure when tested in the Phambili Phase 2b study in a subtype C epidemic. MATERIALS AND METHODS: A sieve analysis, which compares breakthrough viruses from placebo and vaccine arms, was performed on 277 near full-length genomes generated from 23 vaccine and 20 placebo recipients. Vaccine coverage was estimated by computing the percentage of 9-mers that were exact matches to the vaccine insert. RESULTS: There was significantly greater protein distances from the vaccine immunogen sequence in Gag (p=0.045) and Nef (p=0.021) in viruses infecting vaccine recipients compared to placebo recipients. Twenty-seven putative sites of vaccine-induced pressure were identified (p<0.05) in Gag (n=10), Pol (n=7) and Nef (n=10), although they did not remain significant after adjustment for multiple comparisons. We found the epitope sieve effect in Step was driven by HLA A∗02:01; an allele which was found in low frequency in Phambili participants compared to Step participants. Furthermore, the coverage of the vaccine against subtype C Phambili viruses was 31%, 46% and 14% for Gag, Pol and Nef, respectively, compared to subtype B Step virus coverage of 56%, 61% and 26%, respectively. DISCUSSION: This study presents evidence of sieve effects in Gag and Nef; however could not confirm effects on specific amino acid sites. We propose that this weaker signal of vaccine immune pressure detected in the Phambili study compared to the Step study may have been influenced by differences in host genetics (HLA allele frequency) and reduced impact of vaccine-induced immune responses due to mismatch between the viral subtype in the vaccine and infecting subtypes.
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Vacunas contra el SIDA/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Inmunidad Activa , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/administración & dosificación , Adenoviridae , Estudios de Cohortes , Método Doble Ciego , Epítopos/genética , Epítopos/inmunología , Femenino , Frecuencia de los Genes , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Humanos , Masculino , Tamaño de la Muestra , Cobertura de Vacunación , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunologíaRESUMEN
OBJECTIVES: Rapid on-site evaluation (ROSE) of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) followed by a subsequent preliminary adequacy assessment and a preliminary diagnosis, was performed at Aarhus University Hospital by biomedical scientists (BMS). The aim of this study was to evaluate the BMS accuracy of ROSE adequacy assessment, the preliminary adequacy assessment and the preliminary diagnosis as compared with the cytopathologist-rendered final adequacy assessment and final diagnosis. METHODS: The BMS-rendered assessments for 717 sites from 319 consecutive patients over a 4-month period were compared with the cytopathologist-rendered assessments. Comparisons of adequacy and preliminary diagnoses were based on inter-observer Cohen's Kappa coefficient with a 95% confidence interval (CI). RESULTS: Strong correlations between ROSE and final adequacy assessments [Kappa coefficient of 0.90 (CI: 0.85-0.96)] and between the preliminary and final adequacy assessments [Kappa coefficient of 0.93 (CI: 0.87-0.99)] were found. As for the correlation between the preliminary and final diagnoses, the Kappa coefficient was 0.99 (CI: 0.98-1). CONCLUSION: Both ROSE and preliminary adequacy assessments as well as preliminary diagnoses, all performed by BMS, were highly accurate when compared with the final assessment by the cytopathologist.
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Citodiagnóstico/métodos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Neoplasias Pulmonares/diagnóstico , Adulto , Anciano , Broncoscopía , Femenino , Humanos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Estadificación de NeoplasiasRESUMEN
Reports on reddish carotenoid-based ornaments in female three-spined sticklebacks (Gasterosteus aculeatus) are few, despite the large interest in the species' behaviour, ornamentation, morphology and evolution. We sampled sticklebacks from 17 sites in north-western Europe in this first extensive study on the occurrence of carotenoid-based female pelvic spines and throat ornaments. The field results showed that females, and males, with reddish spines were found in all 17 populations. Specimens of both sexes with conspicuous red spines were found in several of the sites. The pelvic spines of males were more intensely red compared to the females' spines, and large specimens were more red than small ones. Fish infected with the tapeworm (Schistocephalus solidus) had drabber spines than uninfected fish. Both sexes had red spines both during and after the spawning period, but the intensity of the red colour was more exaggerated during the spawning period. As opposed to pelvic spines, no sign of red colour at the throat was observed in any female from any of the 17 populations. A rearing experiment was carried out to estimate a potential genetic component of the pelvic spine ornament by artificial crossing and rearing of 15 family groups during a 12 months period. The results indicated that the genetic component of the red colour at the spines was low or close to zero. Although reddish pelvic spines seem common in populations of stickleback, the potential adaptive function of the reddish pelvic spines remains largely unexplained.
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The aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance.
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Rendimiento Atlético/fisiología , Prueba de Esfuerzo/instrumentación , Prueba de Esfuerzo/métodos , Navíos , Diseño de Equipo , HumanosRESUMEN
Recent lines of inquiry indicate that sedatives can influence the immune system, leading to the concept of sedative-induced immunomodulation. It has been hypothesized that sedatives may alter immune responses by modulating the sympathetic nervous system, however, little information is known regarding the effects of sedatives on regulation of splenic sympathetic nerve discharge (SND), a significant omission based on the functional role that changes in splenic SND exert on splenic cytokine gene expression. The present investigation determined the effect of systemic Dexmedetomidine (Dex) administration on the level of directly-recorded splenic SND and tested the hypothesis that the intravenous administration of Dex would inhibit splenic SND in anesthetized rats. The present results demonstrate for the first time that intravenous Dex administration significantly reduces splenic sympathetic nerve outflow in baroreceptor-intact and sinoaortic-denervated rats, indicating that Dex administration alters the central regulation of splenic SND. The present results provide new information regarding the effect of a centrally-acting alpha2-adrenergic agonist on the level of sympathetic nerve outflow to a secondary lymphoid organ that plays a critical role in peripheral immune responses.
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Dexmedetomidina/farmacología , Hipnóticos y Sedantes/farmacología , Bazo/inervación , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Masculino , Fenilefrina/farmacología , Ratas Endogámicas F344 , Sistema Nervioso Simpático/metabolismo , Simpatomiméticos/farmacologíaRESUMEN
The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth's magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local acceleration). We report measurements from NASA's Van Allen Radiation Belt Storm Probes that clearly distinguish between the two types of acceleration. The observed radial profiles of phase space density are characteristic of local acceleration in the heart of the radiation belts and are inconsistent with a predominantly radial acceleration process.
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OBJECTIVES: Encapsulation or entrapment of cells is increasingly being used in a wide variety of scientific studies for tissue engineering and development of novel medical devices. The effect on cell metabolism of such systems is, in general, not well characterized. In this work, a simple system for monitoring respiration of cells embedded in 3-D alginate cultures was characterized. MATERIALS AND METHODS: T-47D cells were cultured in alginate gels. Oxygen concentration curves were recorded within cell-gel constructs using two different sensor systems, and cell viability and metabolic state were characterized using confocal microscopy and commercially available stains. RESULTS: At sufficient depth within constructs, recorded oxygen concentration curves were not significantly influenced by influx of oxygen through cell-gel layers and oxygen consumption rate could be calculated simply by dividing oxygen loss in the system per time, by the number of cells. This conclusion was supported by a 3-D numeric simulation. For the T-47D cells, the oxygen consumption rate was found to be 61 ± 6 fmol/cell/h, 3-4 times less than has previously been found for these cells, when grown exponentially in monolayer culture. CONCLUSIONS: The experimental set-up presented here may be varied in multiple ways by changing the cell-gel construct 3-D microenvironment, easily allowing investigation of a variety of factors on cell respiration.
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Alginatos/metabolismo , Técnicas de Cultivo de Célula/métodos , Respiración de la Célula/fisiología , Consumo de Oxígeno/fisiología , Oxígeno/metabolismo , Línea Celular , Supervivencia Celular/fisiología , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/metabolismo , Humanos , Hipoxia/metabolismo , Hipoxia/fisiopatologíaRESUMEN
In Milan (MI), the largest city in Northern Italy, the annually average PM2.5 concentration is above 25 µg m(-3), the value that the EU established as a target for 2010, and the upper limit from 2015 onwards (2008/30/CE). Over a three-year period (2006-2009) PM concentrations and chemical compositions were measured in an urban site (MI), a rural site (OB) and a remote site (ASC) in Northern Italy. Chemical characterization (EC/OC, inorganic ions, elements, C20-C32 n-alkanes, C2-C5 mono and dicarboxylic acids, levoglucosan and PAHs) was carried out on PM2.5 samples from the three sites, and PM10 from MI. Molecular markers were used in Chemical Mass Balance (CMB) modelling to estimate the contributions of primary sources to OC, and then PM mass from each source was reconstructed in MI, OB and ASC for different seasons. Estimates of the traffic (TR) source contribution to PM2.5 mass ranged from 4.1 (± 2.0) µg m(-3) during the summer, to 13.3 (± 6.7) µg m(-3) during the winter in MI. TR was the main primary source for PM2.5 concentrations in MI (17-24%). Its contribution was lower at the OB site (7-9%) and at the remote ASC site (3-4%). TR is a local source, while biomass burning (BB) is a diffuse regional source in Northern Italy: during fall and winter, BB was 25-30% and 27-31% of PM2.5 at MI and OB respectively. Other primary sources accounted for a small amount of the PM2.5, i.e. natural gas combustion (0-1%), plant debris (0-4%), road dust (RD=0-4%; but 15% at ASC during winter and 10% of PM10 at MI during summer) and sea salt (0-1%). Secondary inorganic+organic aerosol constituted the major part of the PM2.5 mass during spring and summer (50-65%) at the three sites.
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Contaminantes Atmosféricos/análisis , Ciudades , Monitoreo del Ambiente/estadística & datos numéricos , Modelos Químicos , Material Particulado/análisis , Alcanos/análisis , Ácidos Carboxílicos/análisis , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Cromatografía de Gases y Espectrometría de Masas , Glucosa/análogos & derivados , Glucosa/análisis , Italia , Hidrocarburos Policíclicos Aromáticos/análisis , Estaciones del Año , Espectrometría de Masas en TándemRESUMEN
A novel approach for measuring vertical profiles of HCs and particle number concentrations was described and applied in the low troposphere over Milan (Italy) during typical spring and summer days. Particle profiles yielded nearly homogeneous concentrations below the mixing height, with level-to-ground concentration ratios of 92-97%, while HCs showed a more pronounced decrease (74-95%). Vertical mixing and photochemical loss of HCs were demonstrated to cause these gradients. Much lower concentrations were observed for the profiles above the mixing height, where the HC mixtures showed also a different composition, which was partially explained by the horizontal advection of air with HC sources different to those prevailing at the site. The application of pseudo-first order kinetics for reactions between HCs and the hydroxyl radical allowed for the estimation of the vertical mixing time scale in the order of 100 ± 20 min.
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Contaminantes Atmosféricos/análisis , Polvo/análisis , Monitoreo del Ambiente/métodos , Hidrocarburos/análisis , Monitoreo del Ambiente/instrumentación , Italia , Estaciones del AñoRESUMEN
Peptides influence cardiac dysfunction; however, peptidergic modulation of contractile performance remains relatively uncharacterized. We identified a novel human peptide that modulates mammalian contractile performance. Members of the FMRFamide-related peptide (FaRP) family contain a C-terminal RFamide but structurally variant N-terminal extension. We report human RFamide-related peptide-1 (hRFRP-1) and rat RFRP-1 rapidly and reversibly decreased shortening and relaxation in isolated mammalian cardiac myocytes in a dose dependent manner. The mammalian FaRP, 26RFa, structurally related to RFRP-1 by only an RFamide did not influence myocyte contractile function. The protein kinase C (PKC) inhibitor bisindolylmaleimide-1 blocked hRFRP-1 activity. Pretreatment with pertussis toxin (PTX) did not diminish hRFRP-1 influence on contractile function. In addition, intravenous injection of hRFRP-1 in mice decreased heart rate, stroke volume, ejection fraction, and cardiac output. Collectively these findings are consistent with the conclusion RFRP-1 is an endogenous signaling molecule that activates PKC and acts through a PTX-insensitive pathway to modulate cardiac contractile function. Taken together these negative chronotropic, inotropic, and lusitropic effects of hRFRP-1 are significant; they suggest direct acute cellular and organ-level responses in mammalian heart. This is the first known study to identify a mammalian FaRP with cardio-depressant effects, opening a new area of research on peptidergic modulation of contractile performance. The high degree of RFRP structure conservation from amphibians to mammals, and similarity to invertebrate cardioinhibitory peptides suggests RFRP-1 is involved in important physiological functions. Elucidation of mechanisms involved in hRFRP-1 synthesis, release, and signaling may aid the development of strategies to prevent or attenuate cardiac dysfunction.
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Contracción Miocárdica/efectos de los fármacos , Neuropéptidos/farmacología , Neuropéptidos/fisiología , Animales , Depresión Química , Humanos , Ratones , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/fisiología , Proteína Quinasa C , Conejos , RatasRESUMEN
In view of a new amendment to the European legislative regulation on emissions from two-stroke mopeds a study was carried out to comprehensively characterize exhaust gases of mopeds complying current EURO-2 emission standards. Three mopeds with different engine types (carburetor, direct injection, and electronic carburetion system ECS) where investigated by applying two different driving cycles, the legislative cycle ECE47 and the worldwide motorcycle test cycle WMTC. Thereby, particulate matter (PM), regulated compounds, carbonyls, volatile hydrocarbons (VOC), and particle-associated polyaromatic hydrocarbons (PAH) were analyzed and ozone formation potentials (OFP) as well as toxicity equivalents (TEQ) determined. The ECE47 emission factors for almost all species and moped types were much higher in the nonregulated, prior cold phase than in the hot phase, which is considered for legislation. Great differences for the mopeds could be observed for NO(x), VOC, and PM, whereas discrepancies between the driving cycles ECE47 and WMTC were smaller. In addition, a positive influence on exhaust composition caused by technical modifications of the ECS engine was determined. Results indicate that regulation of total hydrocarbons (THC) alone might not be sufficient to regulate PM, especially for direct injection engines. Moreover, recommendations for a revised future test protocol are demonstrated and discussed, whereby the cold phase and the hot phase are taken into account.
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Vehículos a Motor , Emisiones de Vehículos/análisis , Europa (Continente)RESUMEN
Mytilus edulis and Chlamys islandica were exposed to nominal dispersed crude oil concentrations in the range 0.015-0.25 mg/l for one month. Five biomarkers (enzymatic and cellular responses) were analysed together with bioaccumulation of PAHs at the end of exposure. In both species, PAH tissue residues reflected the exposure concentration measured in the water and lipophilicity determined the bioaccumulation levels. Oil caused biomarker responses in both species but more significant alterations in exposed C. islandica were observed. The relationships between exposure levels and enzymatic responses were apparently complex. The integrated biomarker response related against the exposure levels was U-shaped in both species and no correlation with total PAH body burden was found. For the monitoring of chronic offshore discharges, dose- and time-related events should be evaluated in the selection of biomarkers to apply. From this study, cellular damages appear more fitted than enzymatic responses, transient and more complex to interpret.
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Mytilus edulis/efectos de los fármacos , Pectinidae/efectos de los fármacos , Petróleo/toxicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Océano Atlántico , Biomarcadores/metabolismo , Carga Corporal (Radioterapia) , Catalasa/metabolismo , Monitoreo del Ambiente , Glutatión Transferasa/metabolismo , Mytilus edulis/enzimología , Mar del Norte , Pectinidae/enzimología , Petróleo/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Agua de Mar/química , Pruebas de Toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismoRESUMEN
A method for synthesizing superparamagnetic iron oxide (SPIO) multi-nanoparticle aggregates as molecular magnetic resonance imaging (MRI) contrast agents is described. The approach utilizes organic acid/base interactions in the colloid to induce highly controllable nanoparticle aggregation. Monodisperse aggregates with diameters as large as 100 nm are synthesized by manipulating the interfacial surface chemistry of the SPIO nanoparticles in tetrahydrofuran solvent. Subsequent phospholipid micelle encapsulation yields micellar multi-SPIO (mmSPIO) aggregates with enhanced T(2) relaxivity (368.0 s(-1) mmol(-1) Fe) as compared to micellar single particle SPIO (302.0 s(-1) mmol(-1) Fe). mmSPIO conjugated to anti-CA125 monoclonal antibodies were incubated with ovarian carcinoma cell lines to demonstrate targeted in vitro molecular MRI, resulting in a 66% shortening in T(2) time for CA125 positive NIH:OVCAR-3 cells and a less than 3% change in T(2) time for CA125 negative SK-OV-3 cells. The controllable aggregation of mmSPIO shows potential for the development of molecular MRI contrast agents with optimal sizes for specific diagnostic imaging applications.