14 research outputs found
Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star
Ultralight vector dark matter search using data from the KAGRA O3GK run
Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
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Indocyanine Green Modified Silica Shells for Colon Tumor Marking
Marking of colon tumors for surgery is normally done using India ink, but it cannot be imaged below the tissue surface and there is evidence of serious complications such as abscess, intestinal perforation and inconsistency of injection. A novel infrared marker was developed using FDA approved indocyanine green (ICG) dye and ultrathin hollow silica nanoshells. Using a positively charged amine linker, ICG was non-covalently bound to the shell surface. This non-covalent attachment was shown to be stable under biological conditions. For ultra-thin wall 100 nm diameter silica shells, a bimodal ICG layer of < 3 nm was formed. Conversely, for thicker walls on 2 μm diameter silica shells, the ICG layer was only bound to the outer surface and was 6 nm thick. In vitro testing of fluorescent emission showed the particles with the thinner coating were considerably more efficient, consistent with self-quenching in the thicker ICG coatings due to formation of energy traps. Ex vivo testing showed that ICG bound to the 100 nm hollow silica shells was visible under 1.5 cm of tissue. In vivo experiments demonstrated the ability of ICG bound to 100 nm silica shells to mark tumors accurately with no diffusion in tissue and remain visible for over 12 days
Low Efficiency Upconversion Nanoparticles for High-Resolution Coalignment of Near-Infrared and Visible Light Paths on a Light Microscope
One major technical barrier in working with both NIR and visible light on an optical microscope is obtaining their precise coalignment at the imaging plane position. Current techniques require complex setups and software. Photon upconverting particles (UCPs) can bridge this gap as they are excited by NIR light but emit in the visible range. Here, two different UCPs have been identified, high-efficiency micro540-UCPs and lower efficiency nano545-UCPs are compared, and it is found that the lower efficiency nano-UCPs were superior for precise coalignment of the NIR beam with the visible light path consistent with limited particle-to-particle energy transfer, superlinear power dependence for emission, and much smaller particle size
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Low Efficiency Upconversion Nanoparticles for High-Resolution Coalignment of Near-Infrared and Visible Light Paths on a Light Microscope
One major technical barrier in working with both NIR and visible light on an optical microscope is obtaining their precise coalignment at the imaging plane position. Current techniques require complex setups and software. Photon upconverting particles (UCPs) can bridge this gap as they are excited by NIR light but emit in the visible range. Here, two different UCPs have been identified, high-efficiency micro540-UCPs and lower efficiency nano545-UCPs are compared, and it is found that the lower efficiency nano-UCPs were superior for precise coalignment of the NIR beam with the visible light path consistent with limited particle-to-particle energy transfer, superlinear power dependence for emission, and much smaller particle size
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Low Efficiency Upconversion Nanoparticles for High-Resolution Coalignment of Near-Infrared and Visible Light Paths on a Light Microscope
The combination of near-infrared (NIR) and visible wavelengths in light microscopy for biological studies is increasingly common. For example, many fields of biology are developing the use of NIR for optogenetics, in which an NIR laser induces a change in gene expression and/or protein function. One major technical barrier in working with both NIR and visible light on an optical microscope is obtaining their precise coalignment at the imaging plane position. Photon upconverting particles (UCPs) can bridge this gap as they are excited by NIR light but emit in the visible range via an anti-Stokes luminescence mechanism. Here, two different UCPs have been identified, high-efficiency micro540-UCPs and lower efficiency nano545-UCPs, that respond to NIR light and emit visible light with high photostability even at very high NIR power densities (>25 000 Suns). Both of these UCPs can be rapidly and reversibly excited by visible and NIR light and emit light at visible wavelengths detectable with standard emission settings used for Green Fluorescent Protein (GFP), a commonly used genetically encoded fluorophore. However, the high efficiency micro540-UCPs were suboptimal for NIR and visible light coalignment, due to their larger size and spatial broadening from particle-to-particle energy transfer consistent with a long-lived excited state and saturated power dependence. In contrast, the lower efficiency nano-UCPs were superior for precise coalignment of the NIR beam with the visible light path (∼2 μm versus ∼8 μm beam broadening, respectively) consistent with limited particle-to-particle energy transfer, superlinear power dependence for emission, and much smaller particle size. Furthermore, the nano-UCPs were superior to a traditional two-camera method for NIR and visible light path alignment in an in vivo Infrared-Laser-Evoked Gene Operator (IR-LEGO) optogenetics assay in the budding yeast Saccharomyces cerevisiae. In summary, nano-UCPs are powerful new tools for coaligning NIR and visible light paths on a light microscope
Low Efficiency Upconversion Nanoparticles for High-Resolution Coalignment of Near-Infrared and Visible Light Paths on a Light Microscope
The combination of near-infrared (NIR) and visible wavelengths in light microscopy for biological studies is increasingly common. For example, many fields of biology are developing the use of NIR for optogenetics, in which an NIR laser induces a change in gene expression and/or protein function. One major technical barrier in working with both NIR and visible light on an optical microscope is obtaining their precise coalignment at the imaging plane position. Photon upconverting particles (UCPs) can bridge this gap as they are excited by NIR light but emit in the visible range via an anti-Stokes luminescence mechanism. Here, two different UCPs have been identified, high-efficiency micro540-UCPs and lower efficiency nano545-UCPs, that respond to NIR light and emit visible light with high photostability even at very high NIR power densities (>25 000 Suns). Both of these UCPs can be rapidly and reversibly excited by visible and NIR light and emit light at visible wavelengths detectable with standard emission settings used for Green Fluorescent Protein (GFP), a commonly used genetically encoded fluorophore. However, the high efficiency micro540-UCPs were suboptimal for NIR and visible light coalignment, due to their larger size and spatial broadening from particle-to-particle energy transfer consistent with a long-lived excited state and saturated power dependence. In contrast, the lower efficiency nano-UCPs were superior for precise coalignment of the NIR beam with the visible light path (∼2 μm versus ∼8 μm beam broadening, respectively) consistent with limited particle-to-particle energy transfer, superlinear power dependence for emission, and much smaller particle size. Furthermore, the nano-UCPs were superior to a traditional two-camera method for NIR and visible light path alignment in an in vivo Infrared-Laser-Evoked Gene Operator (IR-LEGO) optogenetics assay in the budding yeast Saccharomyces cerevisiae. In summary, nano-UCPs are powerful new tools for coaligning NIR and visible light paths on a light microscope
pydantic/pydantic: v2.5.2 2023-11-22
<h2>v2.5.2 (2023-11-22)</h2>
<p><a href="https://github.com/pydantic/pydantic/releases/tag/v2.5.2">GitHub release</a></p>
<h3>What's Changed</h3>
<h4>Packaging</h4>
<ul>
<li>uprev <code>pydantic-core</code> to 2.14.5</li>
</ul>
<h4>New Features</h4>
<ul>
<li>Add <code>ConfigDict.ser_json_inf_nan</code> by @davidhewitt in <a href="https://github.com/pydantic/pydantic/pull/8159">#8159</a></li>
</ul>
<h4>Fixes</h4>
<ul>
<li>Fix validation of <code>Literal</code> from JSON keys when used as <code>dict</code> key by @sydney-runkle in <a href="https://github.com/pydantic/pydantic-core/pull/1075">pydantic/pydantic-core#1075</a></li>
<li>Fix bug re <code>custom_init</code> on members of <code>Union</code> by @sydney-runkle in <a href="https://github.com/pydantic/pydantic-core/pull/1076">pydantic/pydantic-core#1076</a></li>
<li>Fix <code>JsonValue</code> <code>bool</code> serialization by @sydney-runkle in <a href="https://github.com/pydantic/pydantic/pull/8159">#8190</a></li>
<li>Fix handling of unhashable inputs with <code>Literal</code> in <code>Union</code>s by @sydney-runkle in <a href="https://github.com/pydantic/pydantic-core/pull/1089">pydantic/pydantic-core#1089</a></li>
</ul>
<p>https://github.com/pydantic/pydantic/compare/v2.5.1...v2.5.2/</p>
pydantic/pydantic: v2.5.1 2023-11-15
<h2>v2.5.1 (2023-11-15)</h2>
<p><a href="https://github.com/pydantic/pydantic/releases/tag/v2.5.1">GitHub release</a></p>
<h3>What's Changed</h3>
<h4>Packaging</h4>
<ul>
<li>uprev pydantic-core to 2.14.3 by @samuelcolvin in <a href="https://github.com/pydantic/pydantic/pull/8120">#8120</a></li>
</ul>
<h4>Fixes</h4>
<ul>
<li>Fix package description limit by @dmontagu in <a href="https://github.com/pydantic/pydantic/pull/8097">#8097</a></li>
<li>Fix <code>ValidateCallWrapper</code> error when creating a model which has a @validate_call wrapped field annotation by @sydney-runkle in <a href="https://github.com/pydantic/pydantic/pull/8110">#8110</a></li>
</ul>
<p>Full Changelog: https://github.com/pydantic/pydantic/compare/v2.5.0...v2.5.1/</p>