Detection, quantification, and characterization of polystyrene microplastics and adsorbed bisphenol A contaminant using electroanalytical techniques

The potential applications of electroanalytical techniques for the quantification and size characterization of nonelectroactive polystyrene microplastics is reported, in addition to characterizing the kinetics of adsorption of bisphenol A on these polystyrene microparticles. The individual adsorption events of very diluted polystyrene microparticles dispersions on glassy-carbon microelectrodes produce the blocking of the charge transfer of a mediator (ferrocene-methanol) thus decreasing the current of the recorded chronoamperogram in a stepwise manner. The magnitude of the current steps are in the order of pA values and can be related to the diameter of the plastic microparticles in the size range 0.1 to 10 µm. The frequency of the current steps in the domain time used (120 s) allows to quantify the number concentration of these microparticles in the range 0.005 to 0.500 pM. Electrochemical impedance spectroscopy confirms the adsorption of the polystyrene microplastics on carbon microelectrodes (and to a lesser extent on platinum microelectrodes) under the same experimental conditions as above. On the other hand, the adsorbed microplastics become concentrators of other pollutants found in the environment. The sensitive differential-pulse voltammetry determination of bisphenol A (linear range 0.80–15.00 µM; detection limit 0.24 µM) was used together with a simple separation procedure for studying the adsorption of bisphenol A on polystyrene microparticles. The adsorption capacity (mg of bisphenol A retained per g of the polystyrene microplastics) decreased from approximately 5.7 to 0.8 mg g−1 with increasing dosages of polystyrene microparticles from 0.2 to 1.6 g l−1. The adsorption isotherms were modeled resulting in a monolayer of bisphenol A adsorbed on the microplastics (i.e., best fitted to a Langmuir model)

Light with tunable non-Markovian phase imprint

We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and recording its diffraction pattern after a double slit: In both cases we observe instead of a central intensity maximum a line or cross shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Since these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serve as a testbed to gain a deeper understanding of non-Markovian processes

Regulatory network analysis in estradiol-treated human endothelial cells.

Background/Aims: Estrogen has been reported to have beneficial effects on vascular biology through direct actions on endothelium. Together with transcription factors, miRNAs are the major drivers of gene expression and signaling networks. The objective of this study was to identify a com-prehensive regulatory network (miRNA-transcription factor-downstream genes) that controls the transcriptomic changes observed in endothelial cells exposed to estradiol. Methods: miR-NA/mRNA interactions were assembled using our previous microarray data of human umbilical vein endothelial cells (HUVEC) treated with 17ß- Estradiol (E2) (1 nmol/lL, 24 h). miRNA--mRNA pairings and their associated canonical pathways were determined using Ingenuity Pathway Analysis software. Transcription factors were identified among the miR-NA-regulated genes. Transcription factor downstream target genes were predicted by consensus transcription factor binding sites in the promoter region of E2-regulated genes by using JASPAR and TRANSFAC tools in Enrichr software. Results: miRNA--target pairings were filtered by using differentially expressed miRNAs and mRNAs characterized by a regulatory relationship accord-ing to miRNA target prediction databases. The analysis identified 588 miRNA--target interactions between 102 miRNAs and 588 targets. Specifically, 63 up-regregulated miRNAs interacted with 295 down-regregulated targets, while 39 down-regregulated miRNAs were paired with 293 up-regregulated mRNA targets. Functional characterization of miRNA/mRNA association analy-sis highlighted hypoxia signallignaling, integrin, ephrin receptor signaling, and regulation of actin-based motility by Rho among the canonical pathways regulated by E2 in HUVEC. Tran-scription factors and downstream genes analysis revealed a total of eight networks, including those mediated by JUN and REPIN1, which are associated with cadherin binding and cell adhe-sion molecule binding pathways. Conclusion: This study identifies regulatory networks obtained by integrative microarray analysis and provides additional insights into the way estradiol could regulate endothelial function in human endothelial cells

Abnormal iron metabolism in fibroblasts from a patient with the neurodegenerative disease hereditary ferritinopathy

<p>Abstract</p> <p>Background</p> <p>Nucleotide duplications in exon 4 of the ferritin light polypeptide (FTL) gene cause the autosomal dominant neurodegenerative disease neuroferritinopathy or hereditary ferritinopathy (HF). Pathologic examination of patients with HF has shown abnormal ferritin and iron accumulation in neurons and glia in the central nervous system (CNS) as well as in cells of other organ systems, including skin fibroblasts. To gain some understanding on the molecular basis of HF, we characterized iron metabolism in primary cultures of human skin fibroblasts from an individual with the <it>FTL c.497_498dupTC </it>mutation.</p> <p>Results</p> <p>Compared to normal controls, HF fibroblasts showed abnormal iron metabolism consisting of increased levels of ferritin polypeptides, divalent metal transporter 1, basal iron content and reactive oxygen species, and decreased levels of transferrin receptor-1 and IRE-IRP binding activity.</p> <p>Conclusions</p> <p>Our data indicates that HF fibroblasts replicate the abnormal iron metabolism observed in the CNS of patients with HF. We propose that HF fibroblasts are a unique cellular model in which to study the role of abnormal iron metabolism in the pathogenesis of HF without artifacts derived from over-expression or lack of endogenous translational regulatory elements.</p

IT governance frameworks: A literature review of Brazilian publications

IT (Information Technology) governance has been a widely studied subject. This has generated different definitions and conceptual models to explain it. We conduct a concept-centric literature review based on a literature reference model. We used three literature frameworks to identify key-variables to evaluate and classify Brazilian IT governance publications. These variables were used to classify 90 Brazilian publications from 2004 to 2012. The authors chose Brazil due to its economic growth and companies’ internationalization on the last years. The organizations are fonder to regulatory and compliance marks due to market visibility, driving them towards IT governance practices due to growing dependence on IT. The frameworks used in the country are usually developed abroad - then verification on how they fit with Brazilian organizations is relevant to business management. The study shows that; the most used methodology is the case study; 90% of the papers were written in Portuguese; the IT alignment is cited, but not evaluated; few cases are related to small and medium business; and decision structures are not discussed. The authors conclude presenting a conceptual model summarizing all the models and Brazilian companies’ particularities

Accurate consideration of metal losses at waveguide junctions using admittance and impedance integral equation formulations

[EN] At higher frequencies, metal loss effects in passive waveguide components become more pronounced and hazardous. In this paper, we propose two integral equation techniques, based on the generalized admittance and impedance matrices, for the accurate consideration of losses in the metal walls of waveguide junctions. Both techniques have been evaluated in terms of accuracy and numerical efficiency, and conclusions are drawn regarding the best properties of the admittance parameter formulation. Finally, combining such technique with a classical perturbative method for considering propagation losses, we have successfully predicted all loss effects in two real waveguide filters used for commercial applications.This work has been supported by research projects TIC2000-0591-C03-01 and TIC2000-0591-C03-03 and special action ESP2001-4547-PE.Taroncher Calduch, M.; Hueso, J.; Cogollos, S.; Gimeno. B.; Boria Esbert, VE.; Vidal Pantaleoni, A.; Esteban González, H.... (2005). Accurate consideration of metal losses at waveguide junctions using admittance and impedance integral equation formulations. Radio Science. 40(6):1-12. doi:10.1029/2004RS003225S11240

Reassessing palaeoenvironmental conditions during the Middle-to-Upper Palaeolithic transition in the Cantabrian region (Southwestern Europe)

Climatic and environmental changes have been commonly proposed as driving factors behind the decline of Neanderthals in Europe. The Cantabrian region, in northern Iberia, is a key area for understanding the replacement of Neanderthals by Anatomically Modern Humans, where an early disappearance or Neanderthals in relation to other areas of Iberia has been proposed. To evaluate how climate might have influenced human behaviour during Marine Isotope Stage 3, an accurate review of palaeoecological conditions is required. For the first time, an assessment of the regional available terrestrial proxies linked to archaeo-palaeontological sites, including small vertebrate assemblages, pollen sequences, charcoal data and stable isotope studies on macromammals is undertaken in this region. In addition, records from macrofaunal assemblages and glacial records have also been considered. To standardise the information and allow inter-site comparison, data from pollen and small vertebrate sequences were transformed into quantitative climatic estimations of temperature and precipitation. Results show highly variable climatic shifts between archaeological levels, being consistent with the climatic fluctuations observed in the marine and ice core records. Small mammal assemblages reveal a mosaic landscape of open meadows followed by scattered forested areas. A progressive trend towards aridity from the end of the Mousterian to the early Aurignacian is reflected by changes in arboreal pollen, macromammal species and stable isotopes evidence on ungulates consumed by Neanderthals and Anatomically Modern Humans in the region. This review suggests a decrease in temperatures and rainfall from 48,000 to 44,000 cal BP (after Heinrich Event 5) which coincides with the late Neanderthals in the region and followed by a populational hiatus until 43,000 cal BP. Despite the multiple intra-site environmental proxies available, this study has challenged the fragmentary regional record during this key period for human evolution and reveals that further research is needed to obtain a complete regional high-resolution palaeoenvironmental and palaeoclimatic reconstruction

Iconic-Geometric Nonlinear Registration of a Basal Ganglia Atlas for Deep Brain Stimulation Planning

International audienceThis paper evaluates a nonlinear registration method for warping a 3D histological atlas of the basal ganglia into patient data for deep brain stimulation (DBS) planning. The power of the method is the possibility to combine iconic registration with geometric constraints un-der a unified diffeomorphic framework. This combination aims to ensure robust and accurate atlas-to-patient warping and anatomy-preserving de-formations of stimulation target nuclei. A comparison of the method with a state-of-the-art diffeomorphic registration algorithm reveals how each approach deforms low-contrasted image regions where DBS target nuclei often lie. The technique is applied to T1-weighted magnetic resonance images from a cohort of Parkinsonian subjects, including subjects with standard-size and large ventricles. Results illustrate the effects of iconic or geometric registration alone, as well as how both constraints can be integrated in order to contribute for registration precision enhancement

Gingival neurofibroma in a neurofibromatosis type 1 patient : case report

Neurofibroma is a benign peripheral nerve sheath tumour. It is one of the most frequent tumours of neural origin and its presence is one of the clinical criteria for the diagnosis of type 1 neurofibromatosis (NF-I). Neurofibromatosis type 1 is an autosomal dominantly inherited disease due to an alteration in the long arm of chromosome 17. About 50% of NF-I patients have no family history of the disease. NF-I patients have skin lesions (café au lait spots and neurofibromas) as well as bone malformations and central nervous system tumours. Diagnosis is based on a series of clinical criteria. Gingival neurofibroma in NF-I is uncommon. Treatment of neurofibromas is surgical resection. The aim of this paper is to report a case of NF-I with gingival involvement and to review the literature

Change detection of isolated housing using a new hybrid approach based on object classification with optical and TerraSAR-X data

Optical and microwave high spatial resolution images are now available for a wide range of applications. In this work, they have been applied for the semi-automatic change detection of isolated housing in agricultural areas. This article presents a new hybrid methodology based on segmentation of high-resolution images and image differencing. This new approach mixes the main techniques used in change detection methods and it also adds a final segmentation process in order to classify the change detection product. First, isolated building classification is carried out using only optical data. Then, synthetic aperture radar (SAR) information is added to the classification process, obtaining excellent results with lower complexity cost. Since the first classification step is improved, the total change detection scheme is also enhanced when the radar data are used for classification. Finally, a comparison between the different methods is presented and some conclusions are extracted from the study. © 2011 Taylor & Francis.Vidal Pantaleoni, A.; Moreno Cambroreno, MDR. (2011). Change detection of isolated housing using a new hybrid approach based on object classification with optical and TerraSAR-X data. International Journal of Remote Sensing. 32(24):9621-9635. doi:10.1080/01431161.2011.571297S962196353224BLAES, X., VANHALLE, L., & DEFOURNY, P. (2005). Efficiency of crop identification based on optical and SAR image time series. Remote Sensing of Environment, 96(3-4), 352-365. doi:10.1016/j.rse.2005.03.010Chen, Y., Shi, P., Fung, T., Wang, J., & Li, X. (2007). Object‐oriented classification for urban land cover mapping with ASTER imagery. International Journal of Remote Sensing, 28(20), 4645-4651. doi:10.1080/01431160500444731Dalla Mura, M., Benediktsson, J. A., Bovolo, F., & Bruzzone, L. (2008). An Unsupervised Technique Based on Morphological Filters for Change Detection in Very High Resolution Images. IEEE Geoscience and Remote Sensing Letters, 5(3), 433-437. doi:10.1109/lgrs.2008.917726Dell’Acqua, F., & Gamba, P. (2006). Discriminating urban environments using multiscale texture and multiple SAR images. International Journal of Remote Sensing, 27(18), 3797-3812. doi:10.1080/01431160600557572Haralick, R. M., Shanmugam, K., & Dinstein, I. (1973). Textural Features for Image Classification. IEEE Transactions on Systems, Man, and Cybernetics, SMC-3(6), 610-621. doi:10.1109/tsmc.1973.4309314Im, J., Jensen, J. R., & Tullis, J. A. (2008). Object‐based change detection using correlation image analysis and image segmentation. International Journal of Remote Sensing, 29(2), 399-423. doi:10.1080/01431160601075582Lhomme, S., He, D., Weber, C., & Morin, D. (2009). A new approach to building identification from very‐high‐spatial‐resolution images. International Journal of Remote Sensing, 30(5), 1341-1354. doi:10.1080/01431160802509017LOBO, A., CHIC, O., & CASTERAD, A. (1996). Classification of Mediterranean crops with multisensor data: per-pixel versus per-object statistics and image segmentation. International Journal of Remote Sensing, 17(12), 2385-2400. doi:10.1080/01431169608948779Lu, D., Mausel, P., Brondízio, E., & Moran, E. (2004). Change detection techniques. International Journal of Remote Sensing, 25(12), 2365-2401. doi:10.1080/0143116031000139863Shimabukuro, Y. E., Almeida‐Filho, R., Kuplich, T. M., & de Freitas, R. M. (2007). Quantifying optical and SAR image relationships for tropical landscape features in the Amazônia. International Journal of Remote Sensing, 28(17), 3831-3840. doi:10.1080/01431160701236829Stramondo, S., Bignami, C., Chini, M., Pierdicca, N., & Tertulliani, A. (2006). Satellite radar and optical remote sensing for earthquake damage detection: results from different case studies. International Journal of Remote Sensing, 27(20), 4433-4447. doi:10.1080/01431160600675895Yuan, D., & Elvidge, C. D. (1996). Comparison of relative radiometric normalization techniques. ISPRS Journal of Photogrammetry and Remote Sensing, 51(3), 117-126. doi:10.1016/0924-2716(96)00018-