RESUMO
Strongly interacting topological matter1 exhibits fundamentally new phenomena with potential applications in quantum information technology2,3. Emblematic instances are fractional quantum Hall (FQH) states4, in which the interplay of a magnetic field and strong interactions gives rise to fractionally charged quasi-particles, long-ranged entanglement and anyonic exchange statistics. Progress in engineering synthetic magnetic fields5-21 has raised the hope to create these exotic states in controlled quantum systems. However, except for a recent Laughlin state of light22, preparing FQH states in engineered systems remains elusive. Here we realize a FQH state with ultracold atoms in an optical lattice. The state is a lattice version of a bosonic ν = 1/2 Laughlin state4,23 with two particles on 16 sites. This minimal system already captures many hallmark features of Laughlin-type FQH states24-28: we observe a suppression of two-body interactions, we find a distinctive vortex structure in the density correlations and we measure a fractional Hall conductivity of σH/σ0 = 0.6(2) by means of the bulk response to a magnetic perturbation. Furthermore, by tuning the magnetic field, we map out the transition point between the normal and the FQH regime through a spectroscopic investigation of the many-body gap. Our work provides a starting point for exploring highly entangled topological matter with ultracold atoms29-33.
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Phase transitions are driven by collective fluctuations of a system's constituents that emerge at a critical point1. This mechanism has been extensively explored for classical and quantum systems in equilibrium, whose critical behaviour is described by the general theory of phase transitions. Recently, however, fundamentally distinct phase transitions have been discovered for out-of-equilibrium quantum systems, which can exhibit critical behaviour that defies this description and is not well understood1. A paradigmatic example is the many-body localization (MBL) transition, which marks the breakdown of thermalization in an isolated quantum many-body system as its disorder increases beyond a critical value2-11. Characterizing quantum critical behaviour in an MBL system requires probing its entanglement over space and time4,5,7, which has proved experimentally challenging owing to stringent requirements on quantum state preparation and system isolation. Here we observe quantum critical behaviour at the MBL transition in a disordered Bose-Hubbard system and characterize its entanglement via its multi-point quantum correlations. We observe the emergence of strong correlations, accompanied by the onset of anomalous diffusive transport throughout the system, and verify their critical nature by measuring their dependence on the system size. The correlations extend to high orders in the quantum critical regime and appear to form via a sparse network of many-body resonances that spans the entire system12,13. Our results connect the macroscopic phenomenology of the transition to the system's microscopic structure of quantum correlations, and they provide an essential step towards understanding criticality and universality in non-equilibrium systems1,7,13.
Assuntos
Modelos Teóricos , Teoria Quântica , Partículas Elementares , TermodinâmicaRESUMO
Biosimilars are biologic products that are highly similar to a licensed reference product in terms of quality, safety, and efficacy. SB5 is a biosimilar of Humira® (adalimumab) developed by Samsung Bioepis. To demonstrate its biosimilarity in quality to Humira®, we performed a comprehensive characterization in terms of structure, physicochemical properties, and biological properties following the International Conference on Harmonization, US Food and Drug Administration, and European Medicines Agency guidelines. We analyzed all available batches of SB5 and more than 100 EU- and US-sourced lots of Humira® using state-of-the-art methods whenever possible, and compared the two sets of data. The structural properties comprised primary and higher-order structures and N-glycosylation. The physicochemical characteristics were categorized into liquid chromatographic patterns and electrophoretic pattern concerning size and charge heterogeneity. The biological properties were examined by in vitro functional assays. Overall, SB5 and Humira® were shown to be similar to each other in terms of quality attributes. For some of the quality attributes, minor differences were observed. However, the observed differences have been adequately addressed and demonstrated these do not translate into clinically meaningful differences in terms of safety, purity, and potency.
Assuntos
Adalimumab/química , Adalimumab/imunologia , Medicamentos Biossimilares/química , HumanosRESUMO
Cancer recurrence is the main cause of chemotherapeutic treatment failure. The mechanisms driving cancer recurrence may be due to very rare subpopulation cells, cancer stem-like cells (CSCs). Therefore, the early detection and better treatment of cancer stem-like cells are of great interest. In this study, we investigated how to eliminate the side population cells (SP), which have the characteristics of cancer stem-like cells, and also show chemotherapy resistance. Fluorescence-activated cell sorting (FACS) were used to sort SP and non-SP cells from human liver cancers, Huh-7 Hyaluronic acid (HA), which is an abundant component in the extracellular matrix, is known to involve in proliferation of normal and cancer cells. Herein, we investigated the effect of HA component on chemotherapy against SP cells. Cell growth inhibitory effects of the paclitaxel (PTX) chemotherapy combined with the HA component on SP cells of Huh-7 was determined using the trypan blue dye exclusion test. PTX combined with HA was found to show more increased inhibition of cell growth in both SP and non-SP cells, compared to free PTX treatment. In conclusion, SP cells of Huh-7 shows chemotherapeutic drug resistance due to the over-expressed efflux pumps. HA proposed one of possibilities to overcome the limitation of chemotherapy against cancer stem-like cells.