Experimental Demonstration of Inequivalent Mutually Unbiased Bases.

Quantum measurements based on mutually unbiased bases (MUBs) play crucial roles in foundational studies and quantum information processing. It is known that there exist inequivalent MUBs, but little is known about their operational distinctions, not to say experimental demonstration. In this Letter, by virtue of a simple estimation problem, we experimentally demonstrate the operational distinctions between inequivalent triples of MUBs in dimension 4 based on high-precision photonic systems. The experimental estimation fidelities coincide well with the theoretical predictions with only 0.16% average deviation, which is 25 times less than the difference (4.1%) between the maximum estimation fidelity and the minimum estimation fidelity. Our experiments clearly demonstrate that inequivalent MUBs have different information extraction capabilities and different merits for quantum information processing.

Minimum-Consumption Discrimination of Quantum States via Globally Optimal Adaptive Measurements.

Reducing the average resource consumption is the central quest in discriminating non-orthogonal quantum states for a fixed admissible error rate ϵ. The globally optimal fixed local projective measurement for this task is found to be different from that for previous minimum-error discrimination tasks [S. Slussarenko et al., Phys. Rev. Lett. 118, 030502 (2017)PRLTAO0031-900710.1103/PhysRevLett.118.030502]. To achieve the ultimate minimum average consumption, here we develop a general globally optimal adaptive strategy (GOA) by subtly using the updated posterior probability, which works under any error rate requirements and any one-way measurement restrictions, and can be solved by a convergent iterative relation. First, under the local measurement restrictions, our GOA is solved to serve as the local bound, which saves 16.6 copies (24%) compared with the previously best globally optimal fixed local projective measurement. When the more powerful two-copy collective measurements are allowed, our GOA is experimentally demonstrated to beat the local bound by 3.9 copies (6.0%). By exploiting both adaptivity and collective measurements, our Letter marks an important step toward minimum-consumption quantum state discrimination.

Efficient Experimental Verification of Quantum Gates with Local Operations.

Verifying the correct functioning of quantum gates is a crucial step toward reliable quantum information processing, but it becomes an overwhelming challenge as the system size grows due to the dimensionality curse. Recent theoretical breakthroughs show that it is possible to verify various important quantum gates with the optimal sample complexity of O(1/ε) using local operations only, where ε is the estimation precision. In this Letter, we propose a variant of quantum gate verification (QGV) that is robust to practical gate imperfections and experimentally realize efficient QGV on a 2-qubit controlled-not gate and a 3-qubit Toffoli gate using only local state preparations and measurements. The experimental results show that, by using only 1600 and 2600 measurements on average, we can verify with 95% confidence level that the implemented controlled-not gate and Toffoli gate have fidelities of at least 99% and 97%, respectively. Demonstrating the superior low sample complexity and experimental feasibility of QGV, our work promises a solution to the dimensionality curse in verifying large quantum devices in the quantum era.

Crystalline Hydrate Dehydration Sensing Based on Integrated Terahertz Whispering Gallery Mode Resonators.

Water molecules play a very important role in the hydration and dehydration process of hydrates, which may lead to distinct physical and chemical properties, affecting their availability in practical applications. However, miniaturized, integrated sensors capable of the rapid, sensitive sensing of water molecules in the hydrate are still lacking, limiting their proliferation. Here, we realize the high-sensitivity sensing of water molecules in copper sulfate pentahydrate (CuSO4·5H2O), based on an on-chip terahertz whispering gallery mode resonator (THz-WGMR) fabricated on silicon material via CMOS-compatible technologies. An integrated THz-WGMR with a high-Q factor of 3305 and a resonance frequency of 410.497 GHz was proposed and fabricated. Then, the sensor was employed to distinguish the CuSO4·xH2O (x = 5, 3, 1). The static characterization from the CuSO4·5H2O to the copper sulfate trihydrate (CuSO4·3H2O) experienced blueshifts of 0.55 GHz/µmol, whereas the dehydration process of CuSO4·3H2O to copper sulfate monohydrate (CuSO4·H2O) exhibited blueshifts of 0.21 GHz/µmol. Finally, the dynamic dehydration processes of CuSO4·5H2O to CuSO4·3H2O at different temperatures were monitored. We believe that our proposed THz-WGMR sensors with highly sensitive substance identification capabilities can provide a versatile and integrated platform for studying the transformation between substances, contributing to hydrated/crystal water-assisted biochemical applications.

Acute toxicity of Zanthoxylum bungeanum against two stored product insects and synergistic interactions between two major compounds limonene and linalool.

In order to find and develop new botanical pesticides against storage pests, components of the essential oil (EO) from Zanthoxylum bungeanum were identified by GC-MS and their insecticidal activity against the stored product pests were studied. The EO was obtained by steam distillation. Results showed that EO was rich in limonene (23.67), linalool (21.76) and linalyl anthranilate (10.87). In contact assays, linalool exhibited strongest toxicity to red flour beetle adult (LD50 = 17.06 µg/adult) and larvae (LD50 = 16.42 µg/larvae), and linalool was the most active one against the Lasioderma serricorne (LD50 = 15.36 µg/larvae). Then limonene and linalool showed different levels of fumigant activities against the two insect species. Synergism effect existed in the proportion of contact assays against Tribolium castaneum adults, and additive was observed in the proportion of 7:1 against T. castaneum larvae. This work provides important information for the development and utilization of Z. bungeanum and suggests that the EO of Z. bungeanum has the potential to serve as bio-insecticides for controlling pest damage in stored products.

Pseudogene KRT17P3 drives cisplatin resistance of human NSCLC cells by modulating miR-497-5p/mTOR.

Chemoresistance is a major obstacle in non-small cell lung cancer (NSCLC) treatment. The pseudogene keratin 17 pseudogene 3 (KRT17P3) has been previously shown to be upregulated in lung cancer tissues of patients with cisplatin resistance. In the present study, RT-qPCR was performed to evaluate KRT17P3 levels in plasma samples collected from 30 cisplatin-resistant and 32 cisplatin-sensitive patients. We found that the plasma level of KRT17P3 is upregulated in cisplatin-resistant patients, and the increased expression of plasma KRT17P3 is associated with poor chemotherapy response. Functional studies demonstrated that KRT17P3 overexpression in cultured NSCLC cells increases cell viability and decreases apoptosis upon cisplatin treatment in vitro and in vivo, while KRT17P3 knockdown has the opposite effect. Mechanistically, bioinformatics analysis, RNA immunoprecipitation, and dual luciferase reporter assay indicated that KRT17P3 acts as a molecular sponge for miR-497-5p and relieves the binding of miR-497-5p to its target gene mTOR. Rescue experiments validated the functional interaction between KRT17P3, miR-497-5p, and mTOR. Taken together, our findings indicate that KRT17P3/miR-497-5p/mTOR regulates the chemosensitivity of NSCLC, suggesting a potential therapeutic target for cisplatin-resistant NSCLC patients. KRT17P3 may be a potential peripheral blood marker of NSCLC patients resistant to cisplatin.

"Super-Heisenberg" and Heisenberg Scalings Achieved Simultaneously in the Estimation of a Rotating Field.

The Heisenberg scaling, which scales as N^{-1} in terms of the number of particles or T^{-1} in terms of the evolution time, serves as a fundamental limit in quantum metrology. Better scalings, dubbed as "super-Heisenberg scaling," however, can also arise when the generator of the parameter involves many-body interactions or when it is time dependent. All these different scalings can actually be seen as manifestations of the Heisenberg uncertainty relations. While there is only one best scaling in the single-parameter quantum metrology, different scalings can coexist for the estimation of multiple parameters, which can be characterized by multiple Heisenberg uncertainty relations. We demonstrate the coexistence of two different scalings via the simultaneous estimation of the magnitude and frequency of a field where the best precisions, characterized by two Heisenberg uncertainty relations, scale as T^{-1} and T^{-2}, respectively (in terms of the standard deviation). We show that the simultaneous saturation of two Heisenberg uncertainty relations can be achieved by the optimal protocol, which prepares the optimal probe state, implements the optimal control, and performs the optimal measurement. The optimal protocol is experimentally implemented on an optical platform that demonstrates the saturation of the two Heisenberg uncertainty relations simultaneously, with up to five controls. As the first demonstration of simultaneously achieving two different Heisenberg scalings, our study deepens the understanding on the connection between the precision limit and the uncertainty relations, which has wide implications in practical applications of multiparameter quantum estimation.

Study on clinical application of susceptibility weighted imaging ombined with diffusion weighted imaging in patients with Liver Cirrhosis complicated with small Hepatocellular Carcinoma.

OBJECTIVES: To evaluate the clinical value of susceptibility weighted imaging (SWI) combined with diffusion weighted imaging (DWI) in patients with liver cirrhosis complicated with small hepatocellular carcinoma (SHCC). METHODS: A total of 40 patients with liver cirrhosis and 44 nodules were treated with conventional nuclear magnetic scanning (T1WI, T2WI) and SWI combined with DWI; the results were judged by two senior physicians; the t test, χ2 test, rank sum test, and other methods were used for contrastive analysis of the pathological results of different scanning methods after operation or puncture. RESULTS: Contrast analysis of the different MRI scanning methods and pathological results showed that among the 32 nodules of small hepatocellular carcinoma, 24 cases were diagnosed by conventional MRI, with the coincidence rate being 75%, 30 cases were diagnosed by SWI DWI, with the coincidence rate being 96%; significant difference was found between the two groups (p=0. 04). Significant differences were found in the specificity, sensitivity and accuracy of different scanning methods in the diagnosis of small hepatocellular carcinoma (specificity, accuracy, p=0.04; sensitivity p=0.01). The SWI of small hepatocellular carcinoma nodules showed hyperintensity, and the degree of iron deposition was low. Significant difference was found between small hepatocellular carcinoma nodules and other nodules (comparison of SWI signal degree, p=0.01; comparison of iron deposition degree, p=0.00). CONCLUSION: The SWI of small hepatocellular carcinoma nodules showed hyperintensity, and the degree of iron deposition was low. The coincidence rate of SWI+DWI scanning is higher than that of conventional scanning methods in the diagnosis of small hepatocellular carcinoma, and the difference in specificity, sensitivity and accuracy has obvious advantages. SWI+DWI scanning can improve the detection rate of liver cirrhosis complicated with small hepatocellular carcinoma.

Minimal Tradeoff and Ultimate Precision Limit of Multiparameter Quantum Magnetometry under the Parallel Scheme.

The precise measurement of a magnetic field is one of the most fundamental and important tasks in quantum metrology. Although extensive studies on quantum magnetometry have been carried out over past decades, the ultimate precision that can be achieved for the estimation of all three components of a magnetic field under the parallel scheme remains unknown. This is largely due to the lack of understandings on the incompatibility of the optimal probe states for the estimation of the three components. Here we provide an approach to characterize the minimal tradeoff among the precisions of multiple parameters that arise from the incompatibility of the optimal probe states, which leads to the identification of the ultimate precision limit for the estimation of all three components of a magnetic field under the parallel scheme. The optimal probe state that achieves the ultimate precision is also explicitly constructed. The obtained precision sets a benchmark on the precision of the multiparameter quantum magnetometry under the parallel scheme, which is of fundamental interest and importance in quantum metrology.

Experimental Optimal Orienteering via Parallel and Antiparallel Spins.

Antiparallel spins are superior in orienteering to parallel spins. This intriguing phenomenon is tied to entanglement associated with quantum measurements rather than quantum states. Using photonic systems, we experimentally realize the optimal orienteering protocols based on parallel spins and antiparallel spins, respectively. The optimal entangling measurements for decoding the direction information from parallel spins and antiparallel spins are realized using photonic quantum walks, which is a useful idea that is of wide interest in quantum information processing and foundational studies. Our experiments clearly demonstrate the advantage of antiparallel spins over parallel spins in orienteering. In addition, entangling measurements can extract more information than local measurements even if no entanglement is present in the quantum states.

Experimental Transmission of Quantum Information Using a Superposition of Causal Orders.

Communication in a network generally takes place through a sequence of intermediate nodes connected by communication channels. In the standard theory of communication, it is assumed that the communication network is embedded in a classical spacetime, where the relative order of different nodes is well defined. In principle, a quantum theory of spacetime could allow the order of the intermediate points between sender and receiver to be in a coherent superposition. Here we experimentally realize a tabletop simulation of this exotic possibility on a photonic system, demonstrating high-fidelity transmission of quantum information over two noisy channels arranged in a superposition of two alternative causal orders.

LUCAT1 promotes colorectal cancer tumorigenesis by targeting the ribosomal protein L40-MDM2-p53 pathway through binding with UBA52.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in both men and women in the USA. However, the underlying molecular mechanisms that drive CRC tumorigenesis are still not clear. Several studies have reported that long noncoding RNAs (lncRNAs) have important roles in tumor development. Here, we undertook a transcriptome microarray analysis in 6 pairs of CRC tissues and their corresponding adjacent normal tissues. A total of 1705 differentially expressed lncRNAs were detected in CRC tissues at stages I/II and III/IV (fold change greater than or equal to 2 or less than or equal to 0.5). Among them, we found that the lncRNA lung cancer-associated transcript 1 (LUCAT1) was upregulated in CRC tissues and was closely associated with poor overall survival of CRC patients, through analysis of clinical data and The Cancer Genome Atlas. Functional studies indicated that LUCAT1 promoted CRC cell proliferation, apoptosis, migration, and invasion in vitro and in vivo. Furthermore, knockdown of LUCAT1 rendered CRC cells hypersensitive to oxaliplatin treatment. Mechanistically, bioinformatic analysis indicated that low expression of LUCAT1 was associated with the p53 signaling pathway. Chromatin isolation by RNA purification followed by mass spectrometry and RNA immunoprecipitation revealed that LUCAT1 bound with UBA52, which encodes ubiquitin and 60S ribosomal protein L40 (RPL40). We found that RPL40 functions in the ribosomal protein-MDM2-p53 pathway to regulate p53 expression. Taken together, our findings indicate that suppression of LUCAT1 induces CRC cell cycle arrest and apoptosis by binding UBA52 and activating the RPL40-MDM2-p53 pathway. These results implicate LUCAT1 as a potential prognostic biomarker and therapeutic target for CRC.

Control-Enhanced Sequential Scheme for General Quantum Parameter Estimation at the Heisenberg Limit.

The advantage of quantum metrology has been experimentally demonstrated for phase estimations where the dynamics are commuting. General noncommuting dynamics, however, can have distinct features. For example, the direct sequential scheme, which can achieve the Heisenberg scaling for the phase estimation under commuting dynamics, can have even worse performances than the classical scheme when the dynamics are noncommuting. Here we realize a scalable optimally controlled sequential scheme, which can achieve the Heisenberg precision under general noncommuting dynamics. We also present an intuitive geometrical framework for the controlled scheme and identify sweet spots in time at which the optimal controls used in the scheme can be prefixed without adaptation, which simplifies the experimental protocols significantly. We successfully implement the scheme up to eight controls in an optical platform and demonstrate a precision near the Heisenberg limit. Our work opens the avenue for harvesting the power of quantum control in quantum metrology, and provides a control-enhanced recipe to achieve the Heisenberg precision under general noncommuting dynamics.

Novel lipid side chain modified exenatide analogs emerged prolonged glucoregulatory activity and potential body weight management properties.

Exenatide is known as the first marketed GLP-1 agonist for antidiabetic treatment, but it need twice injection a day because of its fast clearance. This work aims to prolong the half-life of exenatide by modified with novel lipid chain. Four optimized exenatide analogs named as Cys12-Exenatide (1-39)-NH2, Cys40-Exenatide (1-39)-NH2, Cys12-Tyr22-Gln24-Glu28-Arg35-Exenatide (1-39)-NH2 and Tyr22-Gln24-Glu28-Arg35-Cys40-Exenatide (1-39)-NH2 were selected and applied for conjugation. Then a series of evaluations including GLP-1R activation assay were conducted, conjugation C2 was selected for further investigation. Glucoregulatory and insulin secretion assay and hypoglycemic duration test were accessed and showed that C2 was capable of comparable insulinotropic activities and glucose-lowering abilities with those of liraglutide and exenatide. Cell protective effects in INS-1 cells confirmed that C2 had relatively protection effects. Meanwhile, once daily injection of C2 to STZ-induced diabetic mice achieved long-term beneficial effects on glucose tolerance, body weight and blood chemistry. Acute feeding studies were evaluated in DIO mice. These results suggested that C2 is a promising agent for further investigation of its potential to treat diabetes patients with obese.

Overexpressed D2 Dopamine Receptor Inhibits Non-Small Cell Lung Cancer Progression through Inhibiting NF-κB Signaling Pathway.

BACKGROUND/AIMS: Non-small cell lung cancer (NSCLC) is one of the deadliest cancers worldwide. Dopamine receptor D2 (DRD2) has multiple roles in clinical progression of NSCLC and functional maintenance of cancer cells. However, little is known about the molecular mechanism. Here, we clarified whether DRD2 inhibits lung cancer progression and identified the underlying downstream signaling. METHODS: DRD2 mRNA and protein levels were detected in clinical specimens by qRT-PCR and immunohistochemistry, respectively. MTT and colony formation assays were applied to analyze cell proliferation. The underlying molecular mechanism was identified by dual luciferase, western blot, qRT-PCR, cAMP detection, immunoprecipitation, and chromatin immunoprecipitation assays. A murine NSCLC model was used to clarify the role of DRD2 in tumor cell proliferation. RESULTS: We found that DRD2 ablated tumor cell growth. DRD2 expression in NSCLC tissues was lower than in adjacent normal lung tissues. Moreover, DRD2 mRNA and protein levels in NSCLC were negatively correlated with the tumor size, TNM status, and patient overall survival. In vitro experiments showed that disruption of DRD2 promoted the proliferation of NSCLC cell lines A549 and SK-MES-1 by inhibiting the NF-κB signaling pathway. Furthermore, DRD2 overexpression not only blocked lipopolysaccharide-induced A549 and SK-MES-1 cell proliferation and growth, but also inhibited the tumorigenesis in murine xenograft models. CONCLUSION: These results indicate that DRD2 may be a potential therapeutic target for lung cancer patients with high DRD2 expression by ablating the NF-κB signaling pathway.

Experimental demonstration of wave-particle duality relation based on coherence measure.

Wave-particle duality is a typical example of Bohr's complementarity principle that plays a significant role in quantum mechanics. Previous studies used the visibility of an interference pattern to quantify the wave property and used path information to quantify the particle property. However, coherence is the core and basis of the interference phenomenon. If we could use coherence to characterize the wave property, the understanding of wave-particle duality would be strengthened. A recent theoretical work [ Phys. Rev. Lett.116, 160406 (2016)] found two relations between quantum coherence and path information. Here, we demonstrate the new measure of wave-particle duality based on two kinds of coherence measures quantitatively for the first time. The wave property, quantified by the coherence in the l1-norm measure and the relative entropy measure, can be obtained via tomography of the target state, which is encoded in the path degree of freedom of the photons. The particle property, quantified by the path information, can be obtained via the discrimination of detector states, which is encoded in the polarization degree of freedom of the photons. Our work may deepen people's understanding of coherence and provide a new perspective regarding wave-particle duality.

Experimental Cyclic Interconversion between Coherence and Quantum Correlations.

Quantum resource theories seek to quantify sources of nonclassicality that bestow quantum technologies their operational advantage. Chief among these are studies of quantum correlations and quantum coherence. The former isolates nonclassicality in the correlations between systems, and the latter captures nonclassicality of quantum superpositions within a single physical system. Here, we present a scheme that cyclically interconverts between these resources without loss. The first stage converts coherence present in an input system into correlations with an ancilla. The second stage harnesses these correlations to restore coherence on the input system by measurement of the ancilla. We experimentally demonstrate this interconversion process using linear optics. Our experiment highlights the connection between nonclassicality of correlations and nonclassicality within local quantum systems and provides potential flexibilities in exploiting one resource to perform tasks normally associated with the other.

Experimentally Robust Self-testing for Bipartite and Tripartite Entangled States.

Self-testing is a method with which a classical user can certify the state and measurements of quantum systems in a device-independent way. In particular, self-testing of entangled states is of great importance in quantum information processing. An understandable example is that the maximal violation of the Clauser-Horne-Shimony-Holt inequality necessarily implies that the bipartite system shares a singlet. One essential question in self-testing is that, when one observes a nonmaximum violation, how far is the tested state from the target state (which maximally violates a certain Bell inequality)? The answer to this question describes the robustness of the used self-testing criterion, which is highly important in a practical sense. Recently, J. Kaniewski derived two analytic self-testing bounds for bipartite and tripartite systems. In this Letter, we experimentally investigate these two bounds with high-quality two-qubit and three-qubit entanglement sources. The results show that these bounds are valid for various entangled states that we prepared. Thereby, a proof-of-concept demonstration of robust self-testing is achieved, which improves on the previous results significantly.

Experimental demonstration of efficient quantum state tomography of matrix product states.

Quantum state tomography is a key technology for fully determining a quantum state. Unfortunately, standard quantum state tomography is intractable for general many-body quantum states, because the number of measurements and the post-processing time increase exponentially with the size of the system. However, for the matrix product states (MPSs), there exists an efficient method using linearly scaled local measurements and polynomially scaled post-processing times. In this study, we demonstrate the validity of the method in practice by reconstructing a four-photon MPS from its local two- or three-photon reduced-density matrices with the presence of statistical errors and systematical errors in experiment.

Experimental realization of narrowband four-photon Greenberger-Horne-Zeilinger state in a single cold atomic ensemble.

Multi-photon entangled states not only play a crucial role in research on quantum physics but also have many applications in quantum information fields such as quantum computation, quantum communication, and quantum metrology. To fully exploit the multi-photon entangled states, it is important to establish the interaction between entangled photons and matter, which requires that photons have narrow bandwidth. Here, we report on the experimental generation of a narrowband four-photon Greenberger-Horne-Zeilinger state with a fidelity of 64.9% through multiplexing two spontaneous four-wave mixings in a cold Rb85 atomic ensemble. The full bandwidth of the generated GHZ state is about 19.5 MHz. Thus, the generated photons can effectively match the atoms, which are very suitable for building a quantum computation and quantum communication network based on atomic ensembles.