74 research outputs found
On-chip light-scattering enhancement enables high performance single-particle tracking under conventional bright-field microscope
Scattering-based single-particle tracking (S-SPT) has opened new avenues for
highly sensitive label-free detection and characterization of nanoscopic
objects, making it particularly attractive for various analytical applications.
However, a long-standing issue hindering its widespread applicability is its
high technical demands on optical systems. The most promising solution entails
implementing on-chip light-scattering enhancement, but the existing
field-enhancement technology fails as their highly localized field is
insufficient to cover the three-dimensional trajectory of particles within the
interrogation time. Here, we present a straightforward and robust on-chip
microlens-based strategy for light-scattering enhancement, providing an
enhancement range ten times greater than that of near-field optical techniques.
These properties are attributed to the increased long-range optical fields and
complex composite interactions between two closely spaced structures. Thanks to
this strategy, we demonstrate that high-performance S-SPT can be achieved, for
the first time, under a conventional bright-field microscope with illumination
powers over 1,000 times lower than typically required. This significantly
reduces the technical demands of S-SPT, representing a significant step forward
in facilitating its practical application in biophotonics, biosensors,
diagnostics, and other fields.Comment: 29 pages,4 figure
Dynamic Graph Representation Learning via Graph Transformer Networks
Dynamic graph representation learning is an important task with widespread
applications. Previous methods on dynamic graph learning are usually sensitive
to noisy graph information such as missing or spurious connections, which can
yield degenerated performance and generalization. To overcome this challenge,
we propose a Transformer-based dynamic graph learning method named Dynamic
Graph Transformer (DGT) with spatial-temporal encoding to effectively learn
graph topology and capture implicit links. To improve the generalization
ability, we introduce two complementary self-supervised pre-training tasks and
show that jointly optimizing the two pre-training tasks results in a smaller
Bayesian error rate via an information-theoretic analysis. We also propose a
temporal-union graph structure and a target-context node sampling strategy for
efficient and scalable training. Extensive experiments on real-world datasets
illustrate that DGT presents superior performance compared with several
state-of-the-art baselines
Comparison of the efficacy and safety of 10 glucagon-like peptide-1 receptor agonists as add-on to metformin in patients with type 2 diabetes: a systematic review
PurposeThis study aimed to perform a network meta-analysis to objectively evaluate the efficacy and safety of 10 Glucagon-like peptide-1 receptor agonists (GLP-1RAs) in combination with metformin that is approved for use worldwide in patients with type 2 diabetes and to provide evidence-based support and reference for the selection of clinical treatment.MethodsThree databases (PubMed, Embase, and Cochrane Library) were searched from their respective inception until September 30, 2022. Only randomized controlled trials comparing the efficacy and safety of GLP-1RAs for treating type 2 diabetes (T2D) were included. The 10 GLP-1RAs are exenatide (including exenatide twice daily and once weekly), liraglutide, lixisenatide, dulaglutide, PEX168, semaglutide (subcutaneous and oral semaglutide), tirzepatide and albiglutide.Results34 RCTs with 10 GLP-1RAs and 12993 patients were included in the Network Meta-Analysis (NMA). According to the NMA, tirzepatide 15 mg, semaglutide 1.0 mg, PEX168-200μg, oral semaglutide 14 and dulaglutide 1.5 mg reduced HbA1c by -2.23%, -1.57%, -1.12%, -1.10%, -1.09% and body weight by -11.33 kg, -5.99 kg, +0.40 kg, -3.95 kg, -1.87 kg, respectively. There was no significant difference in the rate of adverse events for tirzepatide 15 mg, oral-semaglutide 14 mg, and semaglutide 1.0 mg. PEX168-200μg, tirzepatide 15mg, and oral semaglutide 14mg had Surface Under the Cumulative Ranking (SUCRA) values greater than placebo, and only tirzepatide 15mg and oral semaglutide 14mg were significantly different from placebo in the rate of serious adverse events. All GLP-1RA did not lead to increased incidence of hypoglycemia. Albiglutide 30mg and semaglutide 1.0mg significantly differed from placebo in Adverse Event (AE) withdrawal. Finally, the sensitivity analysis and publication bias analysis results indicate that the study results are reliable.ConclusionThis study’s results showed that GLP-1RAs were effective in lowering HbA1c and reducing body weight without increased incidence of hypoglycemic reactions. In addition, this study may provide reference and evidence-based medical evidence for clinicians to select GLP-1RAs in patients with T2D and high body mass index (BMI). Based on the NMA results, tirzepatide 15mg and semaglutide 1.0mg may be preferred
Search for light dark matter from atmosphere in PandaX-4T
We report a search for light dark matter produced through the cascading decay
of mesons, which are created as a result of inelastic collisions between
cosmic rays and Earth's atmosphere. We introduce a new and general framework,
publicly accessible, designed to address boosted dark matter specifically, with
which a full and dedicated simulation including both elastic and quasi-elastic
processes of Earth attenuation effect on the dark matter particles arriving at
the detector is performed. In the PandaX-4T commissioning data of 0.63
tonneyear exposure, no significant excess over background is observed.
The first constraints on the interaction between light dark matter generated in
the atmosphere and nucleus through a light scalar mediator are obtained. The
lowest excluded cross-section is set at for
dark matter mass of MeV and mediator mass of 300 MeV. The
lowest upper limit of to dark matter decay branching ratio is
A Search for Light Fermionic Dark Matter Absorption on Electrons in PandaX-4T
We report a search on a sub-MeV fermionic dark matter absorbed by electrons
with an outgoing active neutrino using the 0.63 tonne-year exposure collected
by PandaX-4T liquid xenon experiment. No significant signals are observed over
the expected background. The data are interpreted into limits to the effective
couplings between such dark matter and electrons. For axial-vector or vector
interactions, our sensitivity is competitive in comparison to existing
astrophysical bounds on the decay of such dark matter into photon final states.
In particular, we present the first direct detection limits for an axial-vector
(vector) interaction which are the strongest in the mass range from 25 to 45
(35 to 50) keV/c
Multi-tissue integrative analysis of personal epigenomes
Evaluating the impact of genetic variants on transcriptional regulation is a central goal in biological science that has been constrained by reliance on a single reference genome. To address this, we constructed phased, diploid genomes for four cadaveric donors (using long-read sequencing) and systematically charted noncoding regulatory elements and transcriptional activity across more than 25 tissues from these donors. Integrative analysis revealed over a million variants with allele-specific activity, coordinated, locus-scale allelic imbalances, and structural variants impacting proximal chromatin structure. We relate the personal genome analysis to the ENCODE encyclopedia, annotating allele- and tissue-specific elements that are strongly enriched for variants impacting expression and disease phenotypes. These experimental and statistical approaches, and the corresponding EN-TEx resource, provide a framework for personalized functional genomics
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