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https://www.readbyqxmd.com/read/27911038/quantitating-the-cell-turning-images-into-numbers-with-imagej
#1
REVIEW
Ellen T Arena, Curtis T Rueden, Mark C Hiner, Shulei Wang, Ming Yuan, Kevin W Eliceiri
Modern biological research particularly in the fields of developmental and cell biology has been transformed by the rapid evolution of the light microscope. The light microscope, long a mainstay of the experimental biologist, is now used for a wide array of biological experimental scenarios and sample types. Much of the great developments in advanced biological imaging have been driven by the digital imaging revolution with powerful processors and algorithms. In particular, this combination of advanced imaging and computational analysis has resulted in the drive of the modern biologist to not only visually inspect dynamic phenomena, but to quantify the involved processes...
December 2, 2016: Wiley Interdisciplinary Reviews. Developmental Biology
https://www.readbyqxmd.com/read/27910445/the-advanced-ligo-photon-calibrators
#2
S Karki, D Tuyenbayev, S Kandhasamy, B P Abbott, T D Abbott, E H Anders, J Berliner, J Betzwieser, C Cahillane, L Canete, C Conley, H P Daveloza, N De Lillo, J R Gleason, E Goetz, K Izumi, J S Kissel, G Mendell, V Quetschke, M Rodruck, S Sachdev, T Sadecki, P B Schwinberg, A Sottile, M Wade, A J Weinstein, M West, R L Savage
The two interferometers of the Laser Interferometry Gravitational-wave Observatory (LIGO) recently detected gravitational waves from the mergers of binary black hole systems. Accurate calibration of the output of these detectors was crucial for the observation of these events and the extraction of parameters of the sources. The principal tools used to calibrate the responses of the second-generation (Advanced) LIGO detectors to gravitational waves are systems based on radiation pressure and referred to as photon calibrators...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27906321/dm-lcwfc-based-adaptive-optics-system-for-large-aperture-telescopes-imaging-from-visible-to-infrared-waveband
#3
Fei Sun, Zhaoliang Cao, Yukun Wang, Caihua Zhang, Xingyun Zhang, Yong Liu, Quanquan Mu, Li Xuan
Almost all the deformable mirror (DM) based adaptive optics systems (AOSs) used on large aperture telescopes work at the infrared waveband due to the limitation of the number of actuators. To extend the imaging waveband to the visible, we propose a DM and Liquid crystal wavefront corrector (DM/LCWFC) combination AOS. The LCWFC is used to correct the high frequency aberration corresponding to the visible waveband and the aberrations of the infrared are corrected by the DM. The calculated results show that, to a 10 m telescope, DM/LCWFC AOS which contains a 1538 actuators DM and a 404 × 404 pixels LCWFC is equivalent to a DM based AOS with 4057 actuators...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27880760/astronomy-a-black-hole-changes-its-feeding-habits
#4
Stephanie LaMassa
No abstract text is available yet for this article.
December 1, 2016: Nature
https://www.readbyqxmd.com/read/27870609/time-series-decomposition-into-oscillation-components-and-phase-estimation
#5
Takeru Matsuda, Fumiyasu Komaki
Many time series are naturally considered as a superposition of several oscillation components. For example, electroencephalogram (EEG) time series include oscillation components such as alpha, beta, and gamma. We propose a method for decomposing time series into such oscillation components using state-space models. Based on the concept of random frequency modulation, gaussian linear state-space models for oscillation components are developed. In this model, the frequency of an oscillator fluctuates by noise...
November 21, 2016: Neural Computation
https://www.readbyqxmd.com/read/27857377/autonomous-absolute-calibration-of-an-iccd-camera-in-single-photon-detection-regime
#6
Luo Qi, Felix Just, Gerd Leuchs, Maria V Chekhova
Intensified charge coupled device (ICCD) cameras are widely used in vari-ous applications such as microscopy, astronomy, spectroscopy. Often they are used as single-photon detectors, with thresholding being an essential part of the readout. In this paper, we measure the quantum efficiency of an ICCD camera in the single-photon de-tection mode using the Klyshko absolute calibration technique. The quantum efficiency is obtained as a function of the threshold value and of the wavelength of the detected light. In addition, we study the homogeneity of the photon sensitivity over the camera chip area...
November 14, 2016: Optics Express
https://www.readbyqxmd.com/read/27831865/the-spurs-algorithm-for-resampling-an-irregularly-sampled-signal-onto-a-cartesian-grid
#7
Amir Kiperwas, Daniel Rosenfeld, Yonina C Eldar
We present an algorithm for resampling a function from its values on a non-Cartesian grid onto a Cartesian grid. This problem arises in many applications such as MRI, CT, radio astronomy and geophysics. Our algorithm, termed SParse Uniform ReSampling (SPURS), employs methods from modern sampling theory to achieve a small approximation error while maintaining low computational cost. The given non-Cartesian samples are projected onto a selected intermediate subspace, spanned by integer translations of a compactly supported kernel function...
November 1, 2016: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/27808189/astronomy-small-stars-host-water-worlds
#8
(no author information available yet)
No abstract text is available yet for this article.
November 2, 2016: Nature
https://www.readbyqxmd.com/read/27805670/single-shot-diffraction-limited-imaging-through-scattering-layers-via-bispectrum-analysis
#9
Tengfei Wu, Ori Katz, Xiaopeng Shao, Sylvain Gigan
Recently introduced speckle correlations-based techniques enable noninvasive imaging of objects hidden behind scattering layers. In these techniques, the hidden object Fourier amplitude is retrieved from the scattered light autocorrelation, and the lost Fourier phase is recovered via iterative phase-retrieval algorithms, which suffer from convergence to wrong local minimums solutions and cannot solve ambiguities in object orientation. Here, inspired by notions used in astronomy, we experimentally demonstrate that in addition to Fourier amplitude, the object-phase information is naturally and inherently encoded in the scattered light bispectrum (the Fourier transform of triple correlation) and can also be extracted from a single high-resolution speckle pattern, based on which we present a single-shot imaging scheme to deterministically and unambiguously retrieve diffraction-limited images of objects hidden behind scattering layers...
November 1, 2016: Optics Letters
https://www.readbyqxmd.com/read/27782551/q-band-4-state-phase-shifter-in-planar-technology-circuit-design-and-performance-analysis
#10
E Villa, J Cagigas, B Aja, L de la Fuente, E Artal
A 30% bandwidth phase shifter with four phase states is designed to be integrated in a radio astronomy receiver. The circuit has two 90° out-of-phase microwave phase-shifting branches which are combined by Wilkinson power dividers. Each branch is composed of a 180° phase shifter and a band-pass filter. The 180° phase shifter is made of cascaded hybrid rings with microwave PIN diodes as switching devices. The 90° phase shift is achieved with the two band-pass filters. Experimental characterization has shown significant results, with average phase shift values of -90...
September 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27762367/astronomy-two-stars-have-three-disks
#11
(no author information available yet)
No abstract text is available yet for this article.
October 19, 2016: Nature
https://www.readbyqxmd.com/read/27734859/astronomy-strange-fading-star-probed
#12
(no author information available yet)
No abstract text is available yet for this article.
October 12, 2016: Nature
https://www.readbyqxmd.com/read/27708314/astronomy-how-black-hole-obscures-itself
#13
(no author information available yet)
No abstract text is available yet for this article.
October 5, 2016: Nature
https://www.readbyqxmd.com/read/27708296/astronomy-magnetism-drives-star-birth
#14
(no author information available yet)
No abstract text is available yet for this article.
October 5, 2016: Nature
https://www.readbyqxmd.com/read/27703152/thermopile-detector-of-light-ellipticity
#15
Feng Lu, Jongwon Lee, Aiting Jiang, Seungyong Jung, Mikhail A Belkin
Polarimetric imaging is widely used in applications from material analysis to biomedical diagnostics, vision and astronomy. The degree of circular polarization, or light ellipticity, is associated with the S3 Stokes parameter which is defined as the difference in the intensities of the left- and right-circularly polarized components of light. Traditional way of determining this parameter relies on using several external optical elements, such as polarizers and wave plates, along with conventional photodetectors, and performing at least two measurements to distinguish left- and right-circularly polarized light components...
October 5, 2016: Nature Communications
https://www.readbyqxmd.com/read/27687576/wideband-dynamic-microwave-frequency-identification-system-using-a-low-power-ultracompact-silicon-photonic-chip
#16
Maurizio Burla, Xu Wang, Ming Li, Lukas Chrostowski, José Azaña
Photonic-based instantaneous frequency measurement (IFM) of unknown microwave signals offers improved flexibility and frequency range as compared with electronic solutions. However, no photonic platform has ever demonstrated the key capability to perform dynamic IFM, as required in real-world applications. In addition, all demonstrations to date employ bulky components or need high optical power for operation. Here we demonstrate an integrated photonic IFM system that can identify frequency-varying signals in a dynamic manner, without any need for fast measurement instrumentation...
2016: Nature Communications
https://www.readbyqxmd.com/read/27680914/daring-chinese-telescope-is-poised-to-transform-astronomy
#17
David Cyranoski
No abstract text is available yet for this article.
September 26, 2016: Nature
https://www.readbyqxmd.com/read/27680911/astronomy-early-star-forming-gas-found
#18
(no author information available yet)
No abstract text is available yet for this article.
September 28, 2016: Nature
https://www.readbyqxmd.com/read/27661935/fault-tolerant-and-finite-error-localization-for-point-emitters-within-the-diffraction-limit
#19
Zong Sheng Tang, Kadir Durak, Alexander Ling
We implement a self-interference technique for determining the separation between two incoherent point sources. This method relies on image inversion interferometry and when used with the appropriate data analytics, it yields an estimate of the separation with finite-error, including the case when the sources overlap completely. The experimental results show that the technique has a good tolerance to noise and misalignment, making it an interesting consideration for high resolution instruments in microscopy or astronomy...
September 19, 2016: Optics Express
https://www.readbyqxmd.com/read/27649179/long-term-continuous-double-station-observation-of-faint-meteor-showers
#20
Stanislav Vítek, Petr Páta, Pavel Koten, Karel Fliegel
Meteor detection and analysis is an essential topic in the field of astronomy. In this paper, a high-sensitivity and high-time-resolution imaging device for the detection of faint meteoric events is presented. The instrument is based on a fast CCD camera and an image intensifier. Two such instruments form a double-station observation network. The MAIA (Meteor Automatic Imager and Analyzer) system has been in continuous operation since 2013 and has successfully captured hundreds of meteors belonging to different meteor showers, as well as sporadic meteors...
2016: Sensors
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