High spatial resolution and high contrast optical speckle imaging with FASTCAM at the ORM

In this paper, we present an original observational approach, which combines, for the first time, traditional speckle imaging with image post-processing to obtain in the optical domain diffraction-limited images with high contrast (1e-5) within 0.5 to 2 arcseconds around a bright star. The post-processing step is based on wavelet filtering an has analogy with edge enhancement and high-pass filtering. Our I-band on-sky results with the 2.5-m Nordic Telescope (NOT) and the lucky imaging instrument FASTCAM show that we are able to detect L-type brown dwarf companions around a solar-type star with a contrast DI~12 at 2" and with no use of any coronographic capability, which greatly simplifies the instrumental and hardware approach. This object has been detected from the ground in J and H bands so far only with AO-assisted 8-10 m class telescopes (Gemini, Keck), although more recently detected with small-class telescopes in the K band. Discussing the advantage and disadvantage of the optical regime for the detection of faint intrinsic fluxes close to bright stars, we develop some perspectives for other fields, including the study of dense cores in globular clusters. To the best of our knowledge this is the first time that high contrast considerations are included in optical speckle imaging approach.Comment: Proceedings of SPIE conference - Ground-based and Airborne Instrumentation for Astronomy III (Conference 7735), San Diego 201

Decoration of squalenoyl-gemcitabine nanoparticles with squalenyl-hydroxybisphosphonate for the treatment of bone tumors

Therapeutic perspectives of bone tumors such as osteosarcom are main restricted due to the inefficacy of current treatments. We propose here the construction of a novel anticancers qualene-based nanomedicine with bone affinity and retention capacity. A squalenyl-hydroxybisphosphonate molecule was synthetized by chemical conjugation of a 1-hydroxyl-1,1-bi-sphosphonatemoiety to the squalenechain. This amphiphilic compound was inserted onto squalenoyl-gemcitabinenano-particles using the nanoprecipitation method. The co-assemblyled to nanoconstructsof 75 nm, with different morphology and colloidal properties. The presence of squalenyl-hydroxybi-sphosphonate enhanced the nanoparticles binding affinity for hydroxyapatite,a mineral present in the bone. Moreover, the in vitro anticancer activity was preserved when tested in commercial and patient-treated derived pedia tricoste osarcomacells. Furtherin vivo studies will shed lighton the potential of these nano medicines for the treatment of bones arcomas

Structure stability in the simple element sodium under pressure

The simple alkali metal Na, that crystallizes in a body-centred cubic structure at ambient pressure, exhibits a wealth of complex phases at extreme conditions as found by experimental studies. The analysis of the mechanism of stabilization of some of these phases, namely, the low-temperature Sm-type phase and the high-pressure cI16 and oP8 phases, shows that they satisfy the criteria for the Hume-Rothery mechanism. These phases appear to be stabilized due to a formation of numerous planes in a Brillouin-Jones zone in the vicinity of the Fermi sphere of Na, which leads to the reduction of the overall electronic energy. For the oP8 phase, this mechanism seems to be working if one assumes that Na becomes divalent metal at this density. The oP8 phase of Na is analysed in comparison with the MnP-type oP8 phases known in binary compounds, as well as in relation to the hP4 structure of the NiAs-type

2nd Crossmmla: Multimodal learning analytics across physical and digital spaces

© 2018 CEUR-WS. All Rights Reserved. Students’ learning is ubiquitous. It happens wherever the learner is rather than being constrained to a specific physical or digital learning space (e.g. the classroom or the institutional LMS respectively). A critical question is: how to integrate and coordinate learning analytics to provide continued support to learning across physical and digital spaces? CrossMMLA is the successor to the Learning Analytics Across Spaces (CrossLAK) and MultiModal Learning Analytics (MMLA) series of workshops that were merged in 2017 after successful cross-pollination between the two communities. Although it may be said that CrossLAK and MMLA perspectives follow different philosophical and practical approaches, they both share a common aim. This aim is: deploying learning analytics innovations that can be used across diverse authentic learning environments whilst learners feature various modalities of interaction or behaviour

Characterization of a possible nosocomial aspergillosis outbreak

ObjectiveTo study the epidemiologic aspects of a suspected outbreak of nosocomial invasive aspergillosis.MethodsSixteen Aspergillus fumigatus strains were isolated from bronchoalveolar washings or sputa of 10 patients during a 9-month period. Furthermore, two environmental samples, isolated in a microbiological screening of the hospital, were also available for analysis. Random amplified polymorphic DNA analysis (RAPD) was carried out.ResultsThe analysis performed by RAPD clearly demonstrated substantial genetic variation among the isolates. Both of the two different primers selected for RAPD analysis (R-108 and AP12h) were able to demonstrate that the strains isolated from all patients infected with the same fungal species and the environmental samples were genotypically distinct. The results by RAPD typing demonstrated that this technique could detect variability among isolates of Aspergillus fumigatus from different patients and even from the same patient.ConclusionsRAPD genotyping proved that the outbreak of invasive aspergillosis consisted of a series of events, non-related, and probably not coming from the same source within the hospital. This type of analysis is an easy, quick and highly discriminatory technique that may help in planning epidemiologic studies of aspergillosis

Impact of the dosimetry approach on the resulting 90Y radioembolization planned absorbed doses based on 99mTc-MAA SPEC T-CT: is there agreement between dosimetry methods?

Background: Prior radioembolization, a simulation using 99mTc-macroaggregated albumin as 90Y-microspheres surrogate is performed. Gamma scintigraphy images (planar, SPECT, or SPECT-CT) are acquired to evaluate intrahepatic 90Y-microspheres distribution and detect possible extrahepatic and lung shunting. These images may be used for pre-treatment dosimetry evaluation to calculate the 90Y activity that would get an optimal tumor response while sparing healthy tissues. Several dosimetry methods are available, but there is still no consensus on the best methodology to calculate absorbed doses. The goal of this study was to retrospectively evaluate the impact of using different dosimetry approaches on the resulting 90Y-radioembolization pre-treatment absorbed dose evaluation based on 99mTc-MAA images. Methods: Absorbed doses within volumes of interest resulting from partition model (PM) and 3D voxel dosimetry methods (3D-VDM) (dose-point kernel convolution and local deposition method) were evaluated. Additionally, a new “Multi-tumor Partition Model” (MTPM) was developed. The differences among dosimetry approaches were evaluated in terms of mean absorbed dose and dose volume histograms within the volumes of interest. Results: Differences in mean absorbed dose among dosimetry methods are higher in tumor volumes than in non-tumoral ones. The differences between MTPM and both 3D-VDM were substantially lower than those observed between PM and any 3D-VDM. A poor correlation and concordance were found between PM and the other studied dosimetry approaches. DVH obtained from either 3D-VDM are pretty similar in both healthy liver and individual tumors. Although no relevant global differences, in terms of absorbed dose in Gy, between both 3D-VDM were found, important voxel-by-voxel differences have been observed. Conclusions: Significant differences among the studied dosimetry approaches for 90Y-radioembolization treatments exist. Differences do not yield a substantial impact in treatment planning for healthy tissue but they do for tumoral liver. An individual segmentation and evaluation of the tumors is essential. In patients with multiple tumors, the application of PM is not optimal and the 3D-VDM or the new MTPM are suggested instead. If a 3D-VDM method is not available, MTPM is the best option. Furthermore, both 3D-VDM approaches may be indistinctly used

Multicolor photometry of ten Seyfert 1 galaxies

We present BVI photometry of ten Seyfert 1 galaxies and narrow band H-alpha images for six of these objects as well. The results indicate that the luminosity sample distribution has an amplitude of almost 4 magnitudes with an average of M_B=-20.7. The observed morphologies are confined to early type galaxies. A barred structure is found in only 2 objects. Despite that early morphological types are dominant in this sample, integrated (B-V) colors are very blue. For instance, the SO galaxies show, on average, a (B-V)=0.78. This effect seems to be caused by the luminosity contribution of the active nucleus and/or the disk to the total luminosity of the galaxy. In the B band, the contribution of the active galactic nucleus to the total luminosity of the galaxy varies from 3% to almost 60% and the bulge to disk luminosity ratio (L_bulge/L_disk) ranges from 0.6 to 22. Signs of tidal interactions seems to be a common characteristic since they are observed in 6 of the objects and one of them seems to be located in a poor cluster not yet identified in the literature. H_alpha extended emission is rare, with only 1 galaxy showing clear evidence of it. Luminosity profile decomposition shows that the model Gauss + bulge + disk properly reproduces the surface brightness of the galaxies. However, in order to account for the luminosity profile, most of the disk galaxies needs the inner truncated exponential form with a central cutoff radius ranging from 3 to 10 kpc. This is interpreted in terms of reddened regions that are well identified in the B-V color maps. These regions present very similar colors among them, with (B-V)~1.2. This fact could be associated to the presence of dust confined in the inner regions of the galaxies.Comment: 14 pages, 25 figures. Accepted to Astronomy & Astrophysic

An anti-ICAM-2 (CD102) monoclonal antibody induces immune-mediated regressions of transplanted ICAM-2-negative colon carcinomas

Monoclonal antibodies (mAbs) can mediate antitumor effects by indirect mechanisms involving antiangiogenesis and up-regulation of the cellular immune response rather than by direct tumor cell destruction. From mAbs raised by immunization of rats with transformed murine endothelial cells, a mAb (EOL4G8) was selected for its ability to eradicate a fraction of established colon carcinomas that did not express the EOL4G8-recognized antigen. The antigen was found to be ICAM-2 (CD102). Antitumor effects of EOL4G8, which required a functional T-cell compartment, were abrogated by depletion of CD8(+) cells and correlated with antitumor CTL activity, whereas only a mild inhibition of angiogenesis was observed. Interestingly, we found that EOL4G8 acting on endothelial ICAM-2 markedly enhances leukotactic factor activity-1-independent adhesion of immature dendritic cells to endothelium-an effect that is at least in part mediated by DC-SIGN (CD209)

Endothelial Progenitor Cells as a Potential Biomarker in Interstitial Lung Disease Associated with Rheumatoid Arthritis

Interstitial lung disease (ILD) increases morbidity and mortality in patients with rheumatoid arthritis (RA). Although the pathogenesis of ILD associated with RA (RA-ILD(+)) remains poorly defined, vascular tissue is crucial in lung physiology. In this context, endothelial progenitor cells (EPC) are involved in endothelial tissue repair. However, little is known about their implication in RA-ILD(+). Accordingly, we aimed to investigate the potential role of EPC related to endothelial damage in RA-ILD(+). EPC quantification in peripheral blood from 80 individuals (20 RA-ILD(+) patients, 25 RA-ILD(-) patients, 21 idiopathic pulmonary fibrosis (IPF) patients, and 14 healthy controls) was performed by flow cytometry. EPC were considered as CD34(+), CD45(low), CD309(+) and CD133(+). A significant increase in EPC frequency in RA-ILD(+) patients, as well as in RA-ILD(-) and IPF patients, was found when compared with controls (p < 0.001, p = 0.02 and p < 0.001, respectively). RA-ILD(+) patients exhibited a higher EPC frequency than the RA-ILD(-) ones (p = 0.003), but lower than IPF patients (p < 0.001). Our results suggest that EPC increase may represent a reparative compensatory mechanism in patients with RA-ILD(+). The degree of EPC frequency may help to identify the presence of ILD in RA patients and to discriminate RA-ILD(+) from IPF