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1.
Phys Rev Lett ; 133(6): 060201, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178451

RESUMEN

Bell's theorem states that the quantum mechanical description of physical quantities cannot be fully explained by local realistic theories, laying a solid basis for various quantum information applications. Hardy's paradox is celebrated as the simplest form of Bell's theorem concerning its "All versus Nothing" approach to test local realism. However, due to experimental imperfections, existing tests of Hardy's paradox require additional assumptions of the experimental systems, and these assumptions constitute potential loopholes for faithfully testing local realistic theories. Here, we experimentally demonstrate Hardy's nonlocality through a photonic entanglement source. By achieving a detection efficiency of 82.2%, a quantum state fidelity of 99.10%, and applying high-speed quantum random number generators for the measurement setting switching, the experiment is implemented in a loophole-free manner. During 6 h of running, a strong violation of P_{Hardy}=4.646×10^{-4} up to 5 standard deviations is observed with 4.32×10^{9} trials. A null hypothesis test shows that the results can be explained by local realistic theories with an upper bound probability of 10^{-16348}. These testing results provide affirmative evidence against local realism, and establish an advancing benchmark for quantum information applications based on Hardy's paradox.

2.
Org Biomol Chem ; 22(37): 7702-7706, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39224970

RESUMEN

The development of facile and convenient atom-economical methods for the preparation of organosulfur compounds from CS2 is a challenging endeavor. Herein, a one-pot, environmentally friendly method to access S-aryl/alkyl dithiocarbamates has been demonstrated by a three-component coupling involving aryl/alkyl thiols, CS2 and amines in the presence of a common base K2CO3. The transformation process can proceed in an H2O-DMAc (3 : 1) mixed solvent without requiring any catalysts or extensive prefunctionalization of reactants. The protocol is operationally simple and affords dithiocarbamates with various moieties (including aryl, aliphatic, heteroaryl and alkenyl) in good yields.

3.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36688771

RESUMEN

The present study aimed to evaluate the effects of delayed harvest and storage length on fermentation products, bacterial community, and metabolic shifts of elephant grass silage. The late-harvested elephant grass (LG) was naturally fermented (NLG) for 1, 3, 7, 15, 30, and 60 days, respectively. After 60-day ensiling, NLG displayed homolactic fermentation with low pH value, butyric acid, and ammonia nitrogen concentrations, and high lactic acid concentration, and ratio of lactic acid to acetic acid. Pseudomonas, Sphingomonas, and Pantoea dominated the bacterial community in LG, but Lactobacillus, Lactococcus, and Pediococcus were the advantageous genera in a 3-day and 60-day NLG. The correlation heatmap revealed that Acetobacter was positively related to acetic acid, ethanol, ammonia nitrogen, and butyric acid concentrations. There were distinct differences in the KEGG (Kyoto Encyclopedia of Genes and Genomes) metabolic profiles of fresh and ensiled LG. Ensiling suppressed the metabolism of amino acid, vitamins, and energy, while promoted the metabolism of carbohydrate. The LG can be well-fermented without additives, but its low crude protein content should not be ignored when applied in agricultural practice. The ensiling process remarkably affected the fermentation quality, bacterial community, and metabolic profiles of NLG.


Asunto(s)
Amoníaco , Ensilaje , Fermentación , Ácido Butírico/metabolismo , Ensilaje/microbiología , Amoníaco/metabolismo , Bacterias , Ácido Acético/metabolismo , Ácido Láctico/metabolismo , Metaboloma
4.
Phys Rev Lett ; 126(5): 050503, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33605771

RESUMEN

Randomness expansion where one generates a longer sequence of random numbers from a short one is viable in quantum mechanics but not allowed classically. Device-independent quantum randomness expansion provides a randomness resource of the highest security level. Here, we report the first experimental realization of device-independent quantum randomness expansion secure against quantum side information established through quantum probability estimation. We generate 5.47×10^{8} quantum-proof random bits while consuming 4.39×10^{8} bits of entropy, expanding our store of randomness by 1.08×10^{8} bits at a latency of about 13.1 h, with a total soundness error 4.6×10^{-10}. Device-independent quantum randomness expansion not only enriches our understanding of randomness but also sets a solid base to bring quantum-certifiable random bits into realistic applications.

5.
Chin Med Sci J ; 35(4): 330-341, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33413749

RESUMEN

Objective Alzheimer's disease (AD) is the most common cause of dementia. The pathophysiology of the disease mostly remains unearthed, thereby challenging drug development for AD. This study aims to screen high throughput gene expression data using weighted co-expression network analysis (WGCNA) to explore the potential therapeutic targets.Methods The dataset of GSE36980 was obtained from the Gene Expression Omnibus (GEO) database. Normalization, quality control, filtration, and soft-threshold calculation were carried out before clustering the co-expressed genes into different modules. Furthermore, the correlation coefficients between the modules and clinical traits were computed to identify the key modules. Gene ontology and pathway enrichment analyses were performed on the key module genes. The STRING database was used to construct the protein-protein interaction (PPI) networks, which were further analyzed by Cytoscape app (MCODE). Finally, validation of hub genes was conducted by external GEO datasets of GSE 1297 and GSE 28146.Results Co-expressed genes were clustered into 27 modules, among which 6 modules were identified as the key module relating to AD occurrence. These key modules are primarily involved in chemical synaptic transmission (GO:0007268), the tricarboxylic acid (TCA) cycle and respiratory electron transport (R-HSA-1428517). WDR47, OXCT1, C3orf14, ATP6V1A, SLC25A14, NAPB were found as the hub genes and their expression were validated by external datasets.Conclusions Through modules co-expression network analyses and PPI network analyses, we identified the hub genes of AD, including WDR47, OXCT1, C3orf14, ATP6V1A, SLC25A14 and NAPB. Among them, three hub genes (ATP6V1A, SLC25A14, OXCT1) might contribute to AD pathogenesis through pathway of TCA cycle.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Bases de Datos Genéticas , Ontología de Genes , Humanos , Mapas de Interacción de Proteínas , Carácter Cuantitativo Heredable , Reproducibilidad de los Resultados
6.
Phys Rev Lett ; 123(20): 203002, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31809070

RESUMEN

Laser cooling is a well-established technique for the creation of ensembles of ultracold neutral atoms or positive ions. This ability has opened many exciting new research fields over the past 40 years. However, no negatively charged ions have been directly laser cooled because a cycling transition is very rare in atomic anions. Efforts of more than a decade currently have La^{-} as the most promising candidate. We report on experimental and theoretical studies supporting Th^{-} as a new promising candidate for laser cooling. The measured and calculated electron affinities of Th are, respectively, 4901.35(48) cm^{-1} and 4832 cm^{-1}, or 0.607 690(60) and 0.599 eV, almost a factor of 2 larger than the previous theoretical value of 0.368 eV. The ground state of Th^{-} is determined to be 6d^{3}7s^{2} ^{4}F_{3/2}^{e} rather than 6d^{2}7s^{2}7p ^{4}G_{5/2}^{o}. The consequence of this is that there are several strong electric dipole transitions between the bound levels arising from configurations 6d^{3}7s^{2} and 6d^{2}7s^{2}7p in Th^{-}. The potential laser-cooling transition is ^{2}S_{1/2}^{o}↔^{4}F_{3/2}^{e} with a wavelength of 2.6 µm. The zero nuclear spin and hence lack of hyperfine structure in Th^{-} reduces the potential complications in laser cooling as encountered in La^{-}, making Th^{-} a new and exciting candidate for laser cooling.

7.
Phys Rev Lett ; 122(12): 120504, 2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30978079

RESUMEN

Finding exponential separation between quantum and classical information tasks is like striking gold in quantum information research. Such an advantage is believed to hold for quantum computing but is proven for quantum communication complexity. Recently, a novel quantum resource called the quantum switch-which creates a coherent superposition of the causal order of events, known as quantum causality-has been harnessed theoretically in a new protocol providing provable exponential separation. We experimentally demonstrate such an advantage by realizing a superposition of communication directions for a two-party distributed computation. Our photonic demonstration employs d-dimensional quantum systems, qudits, up to d=2^{13} dimensions and demonstrates a communication complexity advantage, requiring less than (0.696±0.006) times the communication of any causally ordered protocol. These results elucidate the crucial role of the coherence of communication direction in achieving the exponential separation for the one-way processing task, and open a new path for experimentally exploring the fundamentals and applications of advanced features of indefinite causal structures.

8.
Med Princ Pract ; 28(3): 256-263, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30646003

RESUMEN

OBJECTIVE: To conduct a meta-analysis of evidence from randomized controlled trails (RCTs) of different doses of intravenous immunoglobulin (IVIG) in children with severe hand, foot and mouth disease (HFMD) to provide the scientific basis for clinical practice. METHODS: A search of PubMed-Medline, CNKI, Wanfang, and VIP database (until June 30, 2017) was performed and Software RevMan5.3 was used to evaluate the effect of different doses of IVIG on HFMD in RCTs. We used random-effects models (or fixed-effects models) and generic inverse variance methods to process quantitative data, followed by a leave-one-out method for sensitivity analysis. RESULTS: From a total of 420 entries identified via searches, 8 RCTs involving 1,450 patients were included in the final analysis. The results of the meta-analysis showed that compared with conventional therapy alone, conventional therapy combined with IVIG had shorter fever clearance time, shorter rash regression time, and shorter clinical cure time. Subgroup analyses showed that the high-dose group (1 g/kg/day) had shorter fever clearance time (p < 0.05), shorter rash regression (p< 0.05), shorter remission time of neurological symptoms (p < 0.05), but longer clinical cure time (p > 0.05). CONCLUSION: The high-dose group has a better prognosis; however, the advantages and disadvantages should be carefully considered when deciding the doses in the treatment of severe HFMD.


Asunto(s)
Enfermedad de Boca, Mano y Pie/terapia , Inmunoglobulinas Intravenosas/uso terapéutico , Niño , Preescolar , Terapia Combinada , Relación Dosis-Respuesta a Droga , Exantema/terapia , Femenino , Fiebre/terapia , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunoglobulinas Intravenosas/efectos adversos , Lactante , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión , Índice de Severidad de la Enfermedad
9.
Light Sci Appl ; 13(1): 172, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025829

RESUMEN

Independent controls of various properties of electromagnetic (EM) waves are crucially required in a wide range of applications. Programmable metasurface is a promising candidate to provide an advanced platform for manipulating EM waves. Here, we propose an approach that can arbitrarily control the polarization direction and phases of reflected waves in linear and nonlinear ways using a stacked programmable metasurface. Further, we extend the space-time-coding theory to incorporate the dimension of polarization, which provides an extra degree of freedom for manipulating EM waves. As proof-of-principle application examples, we consider polarization rotation, phase manipulation, and beam steering at linear and nonlinear frequencies. For validation, we design, fabricate, and measure a metasurface sample. The experimental results show good agreement with theoretical predictions and simulations. The proposed approach has a wide range of applications in various areas, such as imaging, data storage, and wireless communication.

10.
Front Psychol ; 15: 1379705, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784620

RESUMEN

Background: The exploration of personality traits in relation to psychological constructs has become increasingly relevant in understanding the mental health of university students (the emerging adulthood). Studies have focused on how dimensions intersect with various psychological parameters. Aim: The study aims to identify distinct personality profiles among university students based on Eysenck's personality dimensions and investigate how these profiles differ across psychological constructs. Method: A quantitative methodology was utilized, involving 708 university students from Wenzhou and Nanjing in China as participants. The research employed the Eysenck Personality Questionnaire along with other psychological measures. Latent Profile Analysis was applied to categorize the participants into distinct personality profiles. Results: Four distinct personality profiles emerged: 'The Reserved Analyst,' 'The Social Diplomat,' 'The Unconventional Pragmatist,' and 'The Impulsive Truth-Teller.' Significant differences were found among these profiles on various psychological constructs. 'The Social Diplomat' exhibited the most adaptive psychological profile, with higher cognitive reappraisal (F = 45.818, p < 0.001, η2 = 0.163), meaning in life (F = 17.764, p < 0.001, η2 = 0.070), and positive coping (F = 40.765, p < 0.001, η2 = 0.148) compared to other profiles. Conversely, 'The Reserved Analyst' showed higher intolerance of uncertainty (F = 13.854, p < 0.001, η2 = 0.056) and state anxiety (F = 26.279, p < 0.001, η2 = 0.101). Conclusion: This study enriches the understanding of personality traits in relation to psychological constructs within the context of university student populations. By identifying distinct personality profiles, it lays the groundwork for developing tailored mental health strategies that cater to the specific needs of different student groups.

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