117 research outputs found
The PCA Lens-Finder: application to CFHTLS
We present the results of a new search for galaxy-scale strong lensing
systems in CFHTLS Wide. Our lens-finding technique involves a preselection of
potential lens galaxies, applying simple cuts in size and magnitude. We then
perform a Principal Component Analysis of the galaxy images, ensuring a clean
removal of the light profile. Lensed features are searched for in the residual
images using the clustering topometric algorithm DBSCAN. We find 1098 lens
candidates that we inspect visually, leading to a cleaned sample of 109 new
lens candidates. Using realistic image simulations we estimate the completeness
of our sample and show that it is independent of source surface brightness,
Einstein ring size (image separation) or lens redshift. We compare the
properties of our sample to previous lens searches in CFHTLS. Including the
present search, the total number of lenses found in CFHTLS amounts to 678,
which corresponds to ~4 lenses per square degree down to i=24.8. This is
equivalent to ~ 60.000 lenses in total in a survey as wide as Euclid, but at
the CFHTLS resolution and depth.Comment: 21 pages, 12 figures, accepted for publication on A&
Dispositional optimism as a correlate of decision-making styles in adolescence
Despite the numerous psychological areas in which optimism has been
studied, including career planning, only a small amount of research has been done to
investigate the relationship between optimism and decision-making styles. Consequently,
we have investigated the role of dispositional optimism as a correlate of different
decision-making styles, in particular, positive for effective styles and negative for
ineffective ones (doubtfulness, procrastination, and delegation). Data were gathered
through questionnaires administered to 803 Italian adolescents in their last 2 years of
high schools with different fields of study, each at the beginning stages of planning
for their professional future. A paper questionnaire was completed containing measures
of dispositional optimism and career-related decision styles, during a vocational
guidance intervention conducted at school. Data were analyzed using stepwise multiple
regression. Results supported the proposed model by showing optimism to be a strong
correlate of decision-making styles, thereby offering important intervention guidelines
aimed at modifying unrealistically negative expectations regarding their future and
helping students learn adaptive decision-making skills
Biofabrication: an overview of the approaches used for printing of living cells
The development of cell printing is vital for establishing biofabrication approaches as clinically relevant tools. Achieving this requires bio-inks which must not only be easily printable, but also allow controllable and reproducible printing of cells. This review outlines the general principles and current progress and compares the advantages and challenges for the most widely used biofabrication techniques for printing cells: extrusion, laser, microvalve, inkjet and tissue fragment printing. It is expected that significant advances in cell printing will result from synergistic combinations of these techniques and lead to optimised resolution, throughput and the overall complexity of printed constructs
Biochip∕laser cell deposition system to assess polarized axonal growth from single neurons and neuron∕glia pairs in microchannels with novel asymmetrical geometries
Axon path-finding plays an important role in normal and pathogenic brain development as well as in neurological regenerative medicine. In both scenarios, axonal growth is influenced by the microenvironment including the soluble molecules and contact-mediated signaling from guiding cells and cellular matrix. Microfluidic devices are a powerful tool for creating a microenvironment at the single cell level. In this paper, an asymmetrical-channel-based biochip, which can be later incorporated into microfluidic devices for neuronal network study, was developed to investigate geometric as well as supporting cell control of polarized axonal growth in forming a defined neuronal circuitry. A laser cell deposition system was used to place single cells, including neuron-glia pairs, into specific microwells of the device, enabling axonal growth without the influence of cytophilic∕phobic surface patterns. Phase microscopy showed that a novel “snag” channel structure influenced axonal growth in the intended direction 4:1 over the opposite direction. In heterotypic experiments, glial cell influence over the axonal growth path was observed with time-lapse microscopy. Thus, it is shown that single cell and heterotypic neuronal path-finding models can be developed in laser patterned biochips
Effect of ablation parameters on infrared pulsed laser deposition of poly(ethylene glycol) films
Effect of ablation parameters on infrared pulsed laser deposition of poly (ethylene glycol) films
Proteomic Analysis of Formalin-Fixed Prostate Cancer Tissue
Proteomic analysis of formalin-fixed paraffin-embedded (FFPE) tissue would enable retrospective biomarker investigations of this vast archive of pathologically characterized clinical samples that exist worldwide. These FFPE tissues are, however, refractory to proteomic investigations utilizing many state of the art methodologies largely due to the high level of covalently cross-linked proteins arising from formalin fixation. A novel tissue microdissection technique has been developed and combined with a method to extract soluble peptides directly from FFPE tissue for mass spectral analysis of prostate cancer (PCa) and benign prostate hyperplasia (BPH). Hundreds of proteins from PCa and BPH tissue were identified, including several known PCa markers such as prostate-specific antigen, prostatic acid phosphatase, and macrophage inhibitory cytokine-1. Quantitative proteomic profiling utilizing stable isotope labeling confirmed similar expression levels of prostate-specific antigen and prostatic acid phosphatase in BPH and PCa cells, whereas the expression of macrophage inhibitory cytokine-1 was found to be greater in PCa as compared with BPH cells
Trait and state anxiety across academic evaluative contexts: development and validation of the MTEA-12 and MSEA-12 scales
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