Disconnected Skeleton: Shape at its Absolute Scale

We present a new skeletal representation along with a matching framework to address the deformable shape recognition problem. The disconnectedness arises as a result of excessive regularization that we use to describe a shape at an attainably coarse scale. Our motivation is to rely on the stable properties of the shape instead of inaccurately measured secondary details. The new representation does not suffer from the common instability problems of traditional connected skeletons, and the matching process gives quite successful results on a diverse database of 2D shapes. An important difference of our approach from the conventional use of the skeleton is that we replace the local coordinate frame with a global Euclidean frame supported by additional mechanisms to handle articulations and local boundary deformations. As a result, we can produce descriptions that are sensitive to any combination of changes in scale, position, orientation and articulation, as well as invariant ones.Comment: The work excluding {\S}V and {\S}VI has first appeared in 2005 ICCV: Aslan, C., Tari, S.: An Axis-Based Representation for Recognition. In ICCV(2005) 1339- 1346.; Aslan, C., : Disconnected Skeletons for Shape Recognition. Masters thesis, Department of Computer Engineering, Middle East Technical University, May 200

A quantum heat engine with coupled superconducting resonators

We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one due to the coupling. A limit cycle, indicating finite power output, emerges in the thermodynamical phase space. The system implements an all-electrical analog of a photonic piston. Instead of mechanical motion, the power output is obtained as a coherent electrical charging in our case. We explore the differences between the quantum and classical descriptions of our system by solving the quantum master equation and classical Langevin equations. Specifically, we calculate the mean number of excitations, second-order coherence, as well as the entropy, temperature, power and mean energy to reveal the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures.Comment: 15 pages, 14 figures, new references adde

Non-parametric comparison of histogrammed two-dimensional data distributions using the Energy Test

When monitoring complex experiments, comparison is often made between regularly acquired histograms of data and reference histograms which represent the ideal state of the equipment. With the larger HEP experiments now ramping up, there is a need for automation of this task since the volume of comparisons could overwhelm human operators. However, the two-dimensional histogram comparison tools available in ROOT have been noted in the past to exhibit shortcomings. We discuss a newer comparison test for two-dimensional histograms, based on the Energy Test of Aslan and Zech, which provides more conclusive discrimination between histograms of data coming from different distributions than methods provided in a recent ROOT release.The Science and Technology Facilities Council, U

Laparoscopic artificial insemination in dairy sheep with chilled semen stored for up to 26 h

Adult East Freisan crossbred (n = 220) and Chios ewes (n = 105) were divided into four groups and inseminated with chilled semen, which had been stored for 7, 13, 20 or 26 h at 5°C. Unilateral intrauterine insemination (50 x 106 spermatozoa in 0.25 ml) was performed with the aid of a laparoscope. Inseminations were carried out 48 – 52 h after pessary removal (30 mg FGA) without detecting estrus. The lambing rates after intrauterine insemination with chilled semen were found to be similar in East Fresian crossbred (40%) and Chios ewes (30%). Intrauterine insemination with chilled semen stored up to 26 h resulted in similar lambing rates; whereas, fertility of Chios ewes tended to decline with increased holding time of chilled semen. From this study, it is concluded that decreasing the storage time of chilled semen at 5°C improves pregnancy in Chios ewes and that East Fresian crossbred ewe’s conception rates to intrauterine insemination with chilled semen was relatively higher than Chios ewes.Key words: Dairy sheep, chilled semen, time of insemination, lambing rate

Annealed Silver-Island Films for Applications in Metal-Enhanced Fluorescence: Interpretation in Terms of Radiating Plasmons

The effects of thermally annealed silver island films have been studied with regard to their potential applicability in applications of metal-enhanced fluorescence, an emerging tool in nano-biotechnology. Silver island films were thermally annealed between 75 and 250°C for several hours. As a function of both time and annealing temperature, the surface plasmon band at ≈420 nm both diminished and was blue shifted. These changes in plasmon resonance have been characterized using both absorption measurements, as well as topographically using Atomic Force Microscopy. Subsequently, the net changes in plasmon absorption are interpreted as the silver island films becoming spherical and growing in height, as well as an increased spacing between the particles. Interestingly, when the annealed surfaces are coated with a fluorescein-labeled protein, significant enhancements in fluorescence are osbserved, scaling with annealing temperature and time. These observations strongly support our recent hypothesis that the extent of metal-enhanced fluorescence is due to the ability of surface plasmons to radiate coupled fluorophore fluorescence. Given that the extinction spectrum of the silvered films is comprised of both an absorption and scattering component, and that these components are proportional to the diameter cubed and to the sixth power, respectively, then larger structures are expected to have a greater scattering contribution to their extinction spectrum and, therefore, more efficiently radiate coupled fluorophore emission. Subsequently, we have been able to correlate our increases in fluorescence emission with an increased particle size, providing strong experiment evidence for our recently reported metal-enhanced fluorescence, facilitated by radiating plasmons hypothesis

The interplay between learner beliefs and foreign language anxiety: insights from the Turkish EFL context

Foreign language learning in classroom settings has long been found to be associated with anxiety (Horwitz, 1986). Though it is known that sources of foreign language anxiety are varied (Young, 1991), whether anxiety is related to learners’ inherent beliefs about language learning is understudied. To this end, the present study examines the possible relationship between learner beliefs and language anxiety in the under-researched Turkish EFL context. A population of university-level Turkish EFL learners (n=153) completed the Beliefs about Language Learning Inventory (BALLI) and the Foreign Language Classroom Anxiety scale (FLCAS). The underlying constructs in both instruments were explored using an Exploratory Factor Analysis (EFA). A series of Pearson Product-Moment Correlation Coefficient (PPMCC) tests were performed on the factor scores from both instruments. The findings revealed that fear of ambiguity was positively linked to classroom performance anxiety and negative feelings towards English. In addition, the more confident learners feel themselves using English, the more desire they seem to have to interact with native speakers. Overall, positive beliefs about language learning may be helpful in reducing anxiety and boosting confidence in language learning. These findings not only enhance our understanding of the complex psychology of language learning but also have important implications for instructed EFL/ESL settings

Characterization of human platelet binding of recombinant T cell receptor ligand

<p>Abstract</p> <p>Background</p> <p>Recombinant T cell receptor ligands (RTLs) are bio-engineered molecules that may serve as novel therapeutic agents for the treatment of neuroinflammatory conditions such as multiple sclerosis (MS). RTLs contain membrane distal α1 plus β1 domains of class II major histocompatibility complex linked covalently to specific peptides that can be used to regulate T cell responses and inhibit experimental autoimmune encephalomyelitis (EAE). The mechanisms by which RTLs impede local recruitment and retention of inflammatory cells in the CNS, however, are not completely understood.</p> <p>Methods</p> <p>We have recently shown that RTLs bind strongly to B cells, macrophages, and dendritic cells, but not to T cells, in an antigenic-independent manner, raising the question whether peripheral blood cells express a distinct RTL-receptor. Our study was designed to characterize the molecular mechanisms by which RTLs bind human blood platelets, and the ability of RTL to modulate platelet function.</p> <p>Results</p> <p>Our data demonstrate that human blood platelets support binding of RTL. Immobilized RTL initiated platelet intracellular calcium mobilization and lamellipodia formation through a pathway dependent upon Src and PI3 kinases signaling. The presence of RTL in solution reduced platelet aggregation by collagen, while treatment of whole blood with RTL prolonged occlusive thrombus formation on collagen.</p> <p>Conclusions</p> <p>Platelets, well-known regulators of hemostasis and thrombosis, have been implicated in playing a major role in inflammation and immunity. This study provides the first evidence that blood platelets express a functional RTL-receptor with a putative role in modulating pathways of neuroinflammation.</p

Ultra-Fast and Sensitive Detection of Non-Typhoidal Salmonella Using Microwave-Accelerated Metal-Enhanced Fluorescence (“MAMEF”)

Certain serovars of Salmonella enterica subsp. enterica cause invasive disease (e.g., enteric fever, bacteremia, septicemia, meningitis, etc.) in humans and constitute a global public health problem. A rapid, sensitive diagnostic test is needed to allow prompt initiation of therapy in individual patients and for measuring disease burden at the population level. An innovative and promising new rapid diagnostic technique is microwave-accelerated metal-enhanced fluorescence (MAMEF). We have adapted this assay platform to detect the chromosomal oriC locus common to all Salmonella enterica subsp. enterica serovars. We have shown efficient lysis of biologically relevant concentrations of Salmonella spp. suspended in bacteriological media using microwave-induced lysis. Following lysis and DNA release, as little as 1 CFU of Salmonella in 1 ml of medium can be detected in <30 seconds. Furthermore the assay is sensitive and specific: it can detect oriC from Salmonella serovars Typhi, Paratyphi A, Paratyphi B, Paratyphi C, Typhimurium, Enteritidis and Choleraesuis but does not detect Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pneumoniae, Haemophilus influenzae or Acinetobacter baumanii. We have also performed preliminary experiments using a synthetic Salmonella oriC oligonucleotide suspended in whole human blood and observed rapid detection when the sample was diluted 1∶1 with PBS. These pre-clinical data encourage progress to the next step to detect Salmonella in blood (and other ordinarily sterile, clinically relevant body fluids)

Multi-Wavelength Observations of GRB 050820A: An Exceptionally Energetic Event Followed from Start to Finish

We present observations of the unusually bright and long gamma-ray burst GRB 050820A, one of the best-sampled broadband data sets in the Swift era. The gamma-ray light curve is marked by a soft precursor pulse some 200 s before the main event; the lack of any intervening emission suggests that it is due to a physical mechanism distinct from the GRB itself. The large time lag between the precursor and the main emission enabled simultaneous observations in the gamma-ray, X-ray, and optical band-passes, something only achieved for a handful of events to date. While the contemporaneous X-rays are the low-energy tail of the prompt emission, the optical does not directly track the gamma-ray flux. Instead, the early-time optical data appear mostly consistent with the forward shock synchrotron peak passing through the optical, and are therefore likely the beginning of the afterglow. On hour time scales after the burst, the X-ray and optical light curves are inconsistent with an adiabatic expansion of the shock into the surrounding region, but rather indicate that there is a period of energy injection. Observations at late times allow us to constrain the collimation angle of the relativistic outflow to theta = 6.8 - 9.3 degrees. Our estimates of both the kinetic energy of the afterglow and the prompt gamma-ray energy release make GRB 050820A one of the most energetic events for which such values could be determined.Comment: Accepted to ApJ; 18 pages, 8 figures; High resolution version available at http://www.srl.caltech.edu/~cenko/public/papers/grb050820a.p