3,464 research outputs found
Cell sorting in a Petri dish controlled by computer vision.
Fluorescence-activated cell sorting (FACS) applying flow
cytometry to separate cells on a molecular basis is a widespread
method. We demonstrate that both fluorescent and unlabeled live
cells in a Petri dish observed with a microscope can be
automatically recognized by computer vision and picked up by a
computer-controlled micropipette. This method can be routinely
applied as a FACS down to the single cell level with a very
high selectivity. Sorting resolution, i.e., the minimum distance
between two cells from which one could be selectively removed
was 50-70 micrometers. Survival rate with a low number of 3T3
mouse fibroblasts and NE-4C neuroectodermal mouse stem cells was
66 +/- 12% and 88 +/- 16%, respectively. Purity of sorted
cultures and rate of survival using NE-4C/NE-GFP-4C co-cultures
were 95 +/- 2% and 62 +/- 7%, respectively. Hydrodynamic
simulations confirmed the experimental sorting efficiency and a
cell damage risk similar to that of normal FACS
Measurement of the antineutrino neutral-current elastic differential cross section
arXiv:1309.7257v1 [hep-ex
Pre-registration of CT pulmonary volumetric image data
Bakalárska práca sa zaoberá predregistráciou pľúcnych objemových CT obrazových dát. Predregistrácia je riešená metódou fázovej korelácie pri rozklade 3D obrazu na 2D rezy usporiadané za sebou. Práca ďalej popisuje geometrické transformácie, interpolácie, výpočet podobnostných kritérií, optimalizáciu registrácie obrazu a proces samotnej registrácie obrazu. Predregistračný softvér je navrhnutý v programovom prostredí MATLAB^®, kde prebieha predregistrácia 3D reálnych CT obrazových dát s dôrazom na rýchlosť procesu.This bachelor thesis is dealing with pre-registration of CT pulmonary volumetric image data. Pre-registration is solved by phase correlation method, which decomposes 3D images into 2D slices arranged in a row. It further describes the geometric transformations, interpolation, calculations of similarity criteria, optimization of registration of images and the image registration process itself. The pre-registration software runs in MATLAB^®, which works with 3D images of real CT image data with an emphasis on process speed.
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Molecular and Microbial Microenvironments in Chronically Diseased Lungs Associated with Cystic Fibrosis.
To visualize the personalized distributions of pathogens and chemical environments, including microbial metabolites, pharmaceuticals, and their metabolic products, within and between human lungs afflicted with cystic fibrosis (CF), we generated three-dimensional (3D) microbiome and metabolome maps of six explanted lungs from three cystic fibrosis patients. These 3D spatial maps revealed that the chemical environments differ between patients and within the lungs of each patient. Although the microbial ecosystems of the patients were defined by the dominant pathogen, their chemical diversity was not. Additionally, the chemical diversity between locales in the lungs of the same individual sometimes exceeded interindividual variation. Thus, the chemistry and microbiome of the explanted lungs appear to be not only personalized but also regiospecific. Previously undescribed analogs of microbial quinolones and antibiotic metabolites were also detected. Furthermore, mapping the chemical and microbial distributions allowed visualization of microbial community interactions, such as increased production of quorum sensing quinolones in locations where Pseudomonas was in contact with Staphylococcus and Granulicatella, consistent with in vitro observations of bacteria isolated from these patients. Visualization of microbe-metabolite associations within a host organ in early-stage CF disease in animal models will help elucidate the complex interplay between the presence of a given microbial structure, antibiotics, metabolism of antibiotics, microbial virulence factors, and host responses.IMPORTANCE Microbial infections are now recognized to be polymicrobial and personalized in nature. Comprehensive analysis and understanding of the factors underlying the polymicrobial and personalized nature of infections remain limited, especially in the context of the host. By visualizing microbiomes and metabolomes of diseased human lungs, we reveal how different the chemical environments are between hosts that are dominated by the same pathogen and how community interactions shape the chemical environment or vice versa. We highlight that three-dimensional organ mapping methods represent hypothesis-building tools that allow us to design mechanistic studies aimed at addressing microbial responses to other microbes, the host, and pharmaceutical drugs
Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi
We report the detection of high-energy gamma-ray emission from two starburst
galaxies using data obtained with the Large Area Telescope on board the Fermi
Gamma-ray Space Telescope. Steady point-like emission above 200 MeV has been
detected at significance levels of 6.8 sigma and 4.8 sigma respectively, from
sources positionally coincident with locations of the starburst galaxies M82
and NGC 253. The total fluxes of the sources are consistent with gamma-ray
emission originating from the interaction of cosmic rays with local
interstellar gas and radiation fields and constitute evidence for a link
between massive star formation and gamma-ray emission in star-forming galaxies.Comment: Submitted to ApJ Letter
Integrated ecological–economic fisheries models—Evaluation, review and challenges for implementation
Marine ecosystems evolve under many interconnected and area-specific pressures. To fulfil society's intensifying and diversifying needs while ensuring ecologically sustainable development, more effective marine spatial planning and broader-scope management of marine resources is necessary. Integrated ecological-economic fisheries models (IEEFMs) of marine systems are needed to evaluate impacts and sustainability of potential management actions and understand, and anticipate ecological, economic and social dynamics at a range of scales from local to national and regional. To make these models most effective, it is important to determine how model characteristics and methods of communicating results influence the model implementation, the nature of the advice that can be provided and the impact on decisions taken by managers. This article presents a global review and comparative evaluation of 35 IEEFMs applied to marine fisheries and marine ecosystem resources to identify the characteristics that determine their usefulness, effectiveness and implementation. The focus is on fully integrated models that allow for feedbacks between ecological and human processes although not all the models reviewed achieve that. Modellers must invest more time to make models user friendly and to participate in management fora where models and model results can be explained and discussed. Such involvement is beneficial to all parties, leading to improvement of mo-dels and more effective implementation of advice, but demands substantial resources which must be built into the governance process. It takes time to develop effective processes for using IEEFMs requiring a long-term commitment to integrating multidisciplinary modelling advice into management decision-making.</p
The Effects of Cocaine on Different Redox Forms of Cysteine and Homocysteine, and on Labile, Reduced Sulfur in the Rat Plasma Following Active versus Passive Drug Injections
Received: 28 November 2012 / Revised: 19 April 2013 / Accepted: 6 May 2013 / Published online: 16 May 2013
The Author(s) 2013. This article is published with open access at Springerlink.comThe aim of the present studies was to evaluate
cocaine-induced changes in the concentrations of different
redox forms of cysteine (Cys) and homocysteine (Hcy),
and products of anaerobic Cys metabolism, i.e., labile,
reduced sulfur (LS) in the rat plasma. The above-mentioned
parameters were determined after i.p. acute and
subchronic cocaine treatment as well as following i.v.
cocaine self-administration using the yoked procedure.
Additionally, Cys, Hcy, and LS levels were measured
during the 10-day extinction training in rats that underwent
i.v. cocaine administration. Acute i.p. cocaine treatment
increased the total and protein-bound Hcy contents,
decreased LS, and did not change the concentrations of Cys
fractions in the rat plasma. In turn, subchronic i.p. cocaine administration significantly increased free Hcy and lowered
the total and protein-bound Cys concentrations while
LS level was unchanged. Cocaine self-administration
enhanced the total and protein-bound Hcy levels, decreased
LS content, and did not affect the Cys fractions. On the
other hand, yoked cocaine infusions did not alter the concentration
of Hcy fractions while decreased the total and
protein-bound Cys and LS content. This extinction training
resulted in the lack of changes in the examined parameters
in rats with a history of cocaine self-administration while in
the yoked cocaine group an increase in the plasma free Cys
fraction and LS was seen. Our results demonstrate for the
first time that cocaine does evoke significant changes in
homeostasis of thiol amino acids Cys and Hcy, and in some
products of anaerobic Cys metabolism, which are dependent
on the way of cocaine administration
Fermi Gamma-ray Imaging of a Radio Galaxy
The Fermi Gamma-ray Space Telescope has detected the gamma-ray glow emanating
from the giant radio lobes of the radio galaxy Centaurus A. The resolved
gamma-ray image shows the lobes clearly separated from the central active
source. In contrast to all other active galaxies detected so far in high-energy
gamma-rays, the lobe flux constitutes a considerable portion (>1/2) of the
total source emission. The gamma-ray emission from the lobes is interpreted as
inverse Compton scattered relic radiation from the cosmic microwave background
(CMB), with additional contribution at higher energies from the
infrared-to-optical extragalactic background light (EBL). These measurements
provide gamma-ray constraints on the magnetic field and particle energy content
in radio galaxy lobes, and a promising method to probe the cosmic relic photon
fields.Comment: 27 pages, includes Supplementary Online Material; corresponding
authors: C.C. Cheung, Y. Fukazawa, J. Knodlseder, L. Stawar
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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