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Klotho controls the brain-immune system interface in the choroid plexus.
Located within the brain's ventricles, the choroid plexus produces cerebrospinal fluid and forms an important barrier between the central nervous system and the blood. For unknown reasons, the choroid plexus produces high levels of the protein klotho. Here, we show that these levels naturally decline with aging. Depleting klotho selectively from the choroid plexus via targeted viral vector-induced knockout in Klotho flox/flox mice increased the expression of multiple proinflammatory factors and triggered macrophage infiltration of this structure in young mice, simulating changes in unmanipulated old mice. Wild-type mice infected with the same Cre recombinase-expressing virus did not show such alterations. Experimental depletion of klotho from the choroid plexus enhanced microglial activation in the hippocampus after peripheral injection of mice with lipopolysaccharide. In primary cultures, klotho suppressed thioredoxin-interacting protein-dependent activation of the NLRP3 inflammasome in macrophages by enhancing fibroblast growth factor 23 signaling. We conclude that klotho functions as a gatekeeper at the interface between the brain and immune system in the choroid plexus. Klotho depletion in aging or disease may weaken this barrier and promote immune-mediated neuropathogenesis
Poly[(μ3-biphenyl-3,3′-dicarboxylÂato)(1,10-phenanthroline)cadmium]
In the title compound, [Cd(C14H8O4)(C12H8N2)]n, the CdII ion is seven-coordinated in a distorted pentaÂgonal–bipyramidal coordination geometry by five O atoms from bridging biphenyl-3,3′-dicarboylate (dpda) ligands and two N atoms from a 1,10-phenanthroline (1,10-phen) ligand. In the crystal, dinuclear units with a Cd⋯Cd separation of 3.8208 (7) Å are observed. Each of these dinuclear units is bridged via 3,3′-bpda in a chelating/chelating and bridging fashion, generating a zigzag chain along the c axis. Neighboring chains are further packed via weak π–π interÂactions between interÂchain parallel 1,10-phen rings [centroid–centroid distance = 3.5197 (9) Å] into a three-dimensional supraÂmolecular architecture
Capture and sorting of multiple cells by polarization-controlled three-beam interference
For the capture and sorting of multiple cells, a sensitive and highly efficient polarization-controlled three-beam interference set-up has been developed. With the theory of superposition of three beams, simulations on the influence of polarization angle upon the intensity distribution and the laser gradient force change with different polarization angles have been carried out. By controlling the polarization angle of the beams, various intensity distributions and different sizes of dots are obtained. We have experimentally observed multiple optical tweezers and the sorting of cells with different polarization angles, which are in accordance with the theoretical analysis. The experimental results have shown that the polarization angle affects the shapes and feature sizes of the interference patterns and the trapping force
QDTrack: Quasi-Dense Similarity Learning for Appearance-Only Multiple Object Tracking
Similarity learning has been recognized as a crucial step for object
tracking. However, existing multiple object tracking methods only use sparse
ground truth matching as the training objective, while ignoring the majority of
the informative regions in images. In this paper, we present Quasi-Dense
Similarity Learning, which densely samples hundreds of object regions on a pair
of images for contrastive learning. We combine this similarity learning with
multiple existing object detectors to build Quasi-Dense Tracking (QDTrack),
which does not require displacement regression or motion priors. We find that
the resulting distinctive feature space admits a simple nearest neighbor search
at inference time for object association. In addition, we show that our
similarity learning scheme is not limited to video data, but can learn
effective instance similarity even from static input, enabling a competitive
tracking performance without training on videos or using tracking supervision.
We conduct extensive experiments on a wide variety of popular MOT benchmarks.
We find that, despite its simplicity, QDTrack rivals the performance of
state-of-the-art tracking methods on all benchmarks and sets a new
state-of-the-art on the large-scale BDD100K MOT benchmark, while introducing
negligible computational overhead to the detector
The ‘credibility paradox’ in China’s science communication: Views from scientific practitioners
In contrast to increasing debates on China’s rising status as a global scientific power, issues of China’s science communication remain under-explored. Based on 21 in-depth interviews in three cities, this article examines Chinese scientists’ accounts of the entangled web of influence which conditions the process of how scientific knowledge achieves (or fails to achieve) its civic authority. A main finding of this study is a ‘credibility paradox’ as a result of the over-politicisation of science and science communication in China. Respondents report that an absence of visible institutional endorsements renders them more public credibility and better communication outcomes. Thus, instead of exploiting formal channels of science communication, scientists interviewed were more keen to act as ‘informal risk communicators’ in grassroots and private events. Chinese scientists’ perspectives on how to earn public support of their research sheds light on the nature and impact of a ‘civic epistemology’ in an authoritarian state
A Cosmological Model with Dark Spinor Source
In this paper, we discuss the system of Friedman-Robertson-Walker metric
coupling with massive nonlinear dark spinors in detail, where the thermodynamic
movement of spinors is also taken into account. The results show that, the
nonlinear potential of the spinor field can provide a tiny negative pressure,
which resists the Universe to become singular. The solution is oscillating in
time and closed in space, which approximately takes the following form
g_{\mu\nu}=\bar R^2(1-\delta\cos t)^2\diag(1,-1,-\sin^2r ,-\sin^2r
\sin^2\theta), with light year, and
. The present time is about .Comment: 13 pages, no figure, to appear in IJMP
Conformational transitions of heteropolymers in dilute solutions
In this paper we extend the Gaussian self-consistent method to permit study
of the equilibrium and kinetics of conformational transitions for
heteropolymers with any given primary sequence. The kinetic equations earlier
derived by us are transformed to a form containing only the mean squared
distances between pairs of monomers. These equations are further expressed in
terms of instantaneous gradients of the variational free energy. The method
allowed us to study exhaustively the stability and conformational structure of
some periodic and random aperiodic sequences. A typical phase diagram of a
fairly long amphiphilic heteropolymer chain is found to contain phases of the
extended coil, the homogeneous globule, the micro-phase separated globule, and
a large number of frustrated states, which result in conformational phases of
the random coil and the frozen globule. We have also found that for a certain
class of sequences the frustrated phases are suppressed. The kinetics of
folding from the extended coil to the globule proceeds through non-equilibrium
states possessing locally compacted, but partially misfolded and frustrated,
structure. This results in a rather complicated multistep kinetic process
typical of glassy systems.Comment: 15 pages, RevTeX, 20 ps figures, accepted for publication in Phys.
Rev.
BID mediates selective killing of APC-deficient cells in intestinal tumor suppression by nonsteroidal antiinflammatory drugs
Colorectal tumorigenesis is driven by genetic alterations in the adenomatous polyposis coli (APC) tumor suppressor pathway and effectively inhibited by nonsteroidal antiinflammatory drugs (NSAIDs). However, how NSAIDs prevent colorectal tumorigenesis has remained obscure. We found that the extrinsic apoptotic pathway and the BH3 interacting-domain death agonist (BID) are activated in adenomas from NSAID-treated patients. Loss of BID abolishes NSAID-mediated tumor suppression, survival benefit, and apoptosis in tumor-initiating stem cells in APC(Min/+) mice. BID-mediated cross-talk between the extrinsic and intrinsic apoptotic pathways is responsible for selective killing of neoplastic cells by NSAIDs. We further demonstrate that NSAIDs induce death receptor signaling in both cancer and normal cells, but only activate BID in cells with APC deficiency and ensuing c-Myc activation. Our results suggest that NSAIDs suppress intestinal tumorigenesis through BID-mediated synthetic lethality triggered by death receptor signaling and gatekeeper mutations, and provide a rationale for developing more effective cancer prevention strategies and agents
Linguistic Structure Guided Context Modeling for Referring Image Segmentation
Referring image segmentation aims to predict the foreground mask of the
object referred by a natural language sentence. Multimodal context of the
sentence is crucial to distinguish the referent from the background. Existing
methods either insufficiently or redundantly model the multimodal context. To
tackle this problem, we propose a "gather-propagate-distribute" scheme to model
multimodal context by cross-modal interaction and implement this scheme as a
novel Linguistic Structure guided Context Modeling (LSCM) module. Our LSCM
module builds a Dependency Parsing Tree suppressed Word Graph (DPT-WG) which
guides all the words to include valid multimodal context of the sentence while
excluding disturbing ones through three steps over the multimodal feature,
i.e., gathering, constrained propagation and distributing. Extensive
experiments on four benchmarks demonstrate that our method outperforms all the
previous state-of-the-arts.Comment: Accepted by ECCV 2020. Code is available at
https://github.com/spyflying/LSCM-Refse
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