9,934 research outputs found
On-chip generation and collectively coherent control of the superposition of the whole family of Dicke states
Integrated quantum photonics has recently emerged as a powerful platform for
generating, manipulating, and detecting entangled photons. Multipartite
entangled states lie at the heart of the quantum physics and are the key
enabling resources for scalable quantum information processing. Dicke state is
an important class of genuinely entangled state, which has been systematically
studied in the light-matter interactions, quantum state engineering and quantum
metrology. Here, by using a silicon photonic chip, we report the generation and
collectively coherent control of the entire family of four-photon Dicke states,
i.e. with arbitrary excitations. We generate four entangled photons from two
microresonators and coherently control them in a linear-optic quantum circuit,
in which the nonlinear and linear processing are achieved in a chip-scale
device. The generated photons are in telecom band, which lays the groundwork
for large-scale photonic quantum technologies for multiparty networking and
metrology.Comment: 19 pages, 4 figures in the main text and 13 figures in the
Supplemental Materia
1-(2-Fluorobenzyl)-1-(2-fluorobenzyloxy)urea
In the title hydroxyurea derivative, C15H14F2N2O2, the dihedral angle between the two benzene rings is 48.64 (19)°. The urea group forms dihedral angles of 48.1 (2) and 79.2 (2)° with the two benzene rings. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds occur, and further N—H⋯O links lead to chains of molecules
Inhibition of proliferation, migration and invasion of human non-small cell lung cancer cell line A549 by phlomisoside F from Phlomis younghusbandii Mukerjee
Purpose: To determine the effect of phlomisoside F (PMF) on the proliferation, migration and invasion of human non-small cell lung cancer cell line A549 and explore the possible mechanisms.Methods: The anti-proliferative effect of PMF on A549 cells was determined by CCK-8. Subsequently, migration and invasion were evaluated by Transwell and Transwell with matrigel assays, respectively. Furthermore, cell cycle and apoptosis were assessed by flow cytometry, while the mechanisms of action were determined by Western blotting.Results: PMF exhibited significant anti-proliferative effect on A549 cells in concentration-dependent and time-dependent manners, with half maximal inhibitory concentration (IC50) of 54.51 μM. Treatment with PMF (10, 20 and 40 μM) for 48 h resulted in significantly decreased migration and invasion in A549 cells. In addition, PMF at concentrations of 25, 50 and 75 μM induced cell cycle arrest in G0/G1phase and enhanced cell apoptosis in A549 cells. Furthermore, caspase-3, caspase-9 and Bax protein expressions were up-regulated while Bacl-2 and COX-2 protein expressions were significantly downregulated at 10, 20 and 40 μM concentrations of PMF.Conclusion: PMF suppresses A549 cell growth, migration and invasion. The mechanism may be related to the induction of mitochondria-mediated apoptosis pathway via regulation of caspase-3, caspase-9, Bcl-2 and Bax expressions, and inhibition of PGE2 synthesis by reducing COX-2 expression.Keywords: Phlomisoside F, Lung cancer, Cell mobility, Apoptosis, PGE2, COX-2 expression, Caspase, Cell cycle arres
How tyramine β-hydroxylase controls the production of octopamine, modulating the mobility of beetles
Biogenic amines perform many kinds of important physiological functions in the central nervous system (CNS) of insects, acting as neuromodulators, neurotransmitters, and neurohormones. The five most abundant types of biogenic amines in invertebrates are dopamine, histamine, serotonin, tyramine, and octopamine (OA). However, in beetles, an important group of model and pest insects, the role of tyramine beta-hydroxylase (T beta H) in the OA biosynthesis pathway and the regulation of behavior remains unknown so far. We therefore investigated the molecular characterization and spatiotemporal expression profiles of T beta H in red flour beetles (Triboliun castaneum). Most importantly, we detected the production of OA and measured the crawling speed of beetles after dsTcT beta H injection. We concluded that TcT beta H controls the biosynthesis amount of OA in the CNS, and this in turn modulates the mobility of the beetles. Our new results provided basic information about the key genes in the OA biosynthesis pathway of the beetles, and expanded our knowledge on the physiological functions of OA in insects
Disturbance Rejection Control for Autonomous Trolley Collection Robots with Prescribed Performance
Trajectory tracking control of autonomous trolley collection robots (ATCR) is
an ambitious work due to the complex environment, serious noise and external
disturbances. This work investigates a control scheme for ATCR subjecting to
severe environmental interference. A kinematics model based adaptive sliding
mode disturbance observer with fast convergence is first proposed to estimate
the lumped disturbances. On this basis, a robust controller with prescribed
performance is proposed using a backstepping technique, which improves the
transient performance and guarantees fast convergence. Simulation outcomes have
been provided to illustrate the effectiveness of the proposed control scheme
The Role of Deubiquitinases in DNA Double-Strand Break Repair
DNA double-strand break (DSB) is a type of the most critical DNA lesions, and if not repaired promptly, it can result in cell death or a wide variety of genetic alterations including genome instability, large- or small-scale deletions, chromosome loss, loss of heterozygosity, and translocations. DSBs are repaired by double-strand break repair (DSBR), including nonhomologous end-joining (NHEJ) and homologous recombination (HR) pathway, and defects in these pathways cause genome instability and promote tumorigenesis. Accumulating evidence has demonstrated that the superfamily of deubiquitinases (DUBs) can regulate the action and stability of DNA repair enzymes involving in DSBR via modifying ubiquitination levels, a reversible posttranslational modification pathway. In this review, we will discuss ubiquitination/deubiquitination modification involving in DSBR genes, the role of DUBs in DSBR and corresponding mechanisms, and the potential effects of this modification on human diseases
Poly[bis(2,2′-bipyridine-κ2 N,N′)deca-μ-oxido-dioxidodicopper(II)tetravanadium(V)]
The title compound, [Cu2V4O12(C10H8N2)2]n, shows a two-dimensional copper–vanadate layer composed of eight-membered rings, each containing four corner-sharing VO4 tetrahedra; these are linked through six pentacoordinated CuII atoms with the 2,2′-bipyridine ligands attached and pointing above and below the plane of the layer. The Cu atom is coordinated by two N donors from the 2,2′-bipyridine ligand and three O atoms from three adjacent VO4 units to form a distorted tetragonal pyramid. These layers are further connected by π–π interactions between interleaving bipyridine ligands of adjacent layers [centroid–centroid distances = 3.63 (1) and 3.68 (1) Å] into a three-dimensional supramolecular structure
- …