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Laser-cooled and trapped atomic ions form an ideal standard for the simulation of interacting quantum spin models. Effective spins are represented by appropriate internal energy levels within each ion, and the spins can be measured with near-perfect efficiency using state-dependent fluorescence techniques. By applying optical fields that exert optical dipole forces on the ions, their Coulomb interaction can be modulated to produce long-range and tunable spin-spin interactions that can be reconfigured by shaping the spectrum and pattern of the laser fields in a prototypical example of a quantum simulator. Here the theoretical mapping of atomic ions to interacting spin systems, the preparation of complex equilibrium states, and the study of dynamical processes in these many-body interacting quantum systems are reviewed, and the use of this platform for optimization and other tasks is discussed. The use of such quantum simulators for studying spin models may inform our understanding of exotic quantum materials and shed light on the behavior of interacting quantum systems that cannot be modeled with conventional computers.

A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long-range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics. Here we show how the appropriate design of laser fields can provide for arbitrary multidimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently available trap technology and is scalable to levels where the classical methods of simulation are intractable. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Yun Wang,1 Fu-xing Lin,2 Yu Zhao,1 Mo-zhen Wang,2 Xue-wu Ge,2 Zheng-xing Gong,1 Dan-dan Bao,1 Yu-fang Gu1 1Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, 2CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China Abstract: Novel submicron core-shell-structured chitosan-based composite particles ­encapsulated with enhanced green fluorescent protein plasmids (pEGFP) were prepared by complex coacervation method. The core was pEGFP-loaded thiolated N-alkylated chitosan (TACS) and the shell was pH- and temperature-responsive hydroxybutyl chitosan (HBC). pEGFP-loaded TACS-HBC composite particles were spherical, and had a mean diameter of approximately 120 nm, as measured by transmission electron microscopy and particle size analyzer. pEGFP showed sustained release in vitro for >15 days. Furthermore, in vitro transfection in human embryonic kidney 293T and human cervix epithelial cells, and in vivo transfection in mice skeletal muscle of loaded pEGFP, were investigated. Results showed that the expression of loaded pEGFP, both in vitro and in vivo, was slow but could be sustained over a long period. pEGFP expression in mice skeletal muscle was sustained for >60 days. This work indicates that these submicron core-shell-structured chitosan-based composite particles could potentially be used as a gene vector for in vivo controlled gene transfection. Keywords: gene therapy, gene transfection, hydroxybutyl chitosan, thiolated N-alkylated chitosan, pEGFP, complex coacervation

Topologically ordered phases of matter elude Landau's symmetry-breaking theory, featuring a variety of intriguing properties such as long-range entanglement and intrinsic robustness against local perturbations. Their extension to periodically driven systems gives rise to exotic new phenomena that are forbidden in thermal equilibrium. Here, we report the observation of signatures of such a phenomenon-a prethermal topologically ordered time crystal-with programmable superconducting qubits arranged on a square lattice. By periodically driving the superconducting qubits with a surface code Hamiltonian, we observe discrete time-translation symmetry breaking dynamics that is only manifested in the subharmonic temporal response of nonlocal logical operators. We further connect the observed dynamics to the underlying topological order by measuring a nonzero topological entanglement entropy and studying its subsequent dynamics. Our results demonstrate the potential to explore exotic topologically ordered nonequilibrium phases of matter with noisy intermediate-scale quantum processors., (© 2024. The Author(s).)

The Asian honey bee ( Apis cerana ) plays a crucial role in providing abundant bee products and in maintaining ecological balance. Despite the availability of the genomic sequence of the Asian honey bee, its transcriptomic information remains largely incomplete. To address this issue, here we constructed three pooled RNA samples from the queen, drone, and worker bees of A. cerana and performed full-length RNA sequencing using Nanopore single-molecule sequencing technology. Ultimately, we obtained 160,811 full-length transcript sequences from 19,859 genes, with 141,189 being novel transcripts, of which 130,367 were functionally annotated. We detected 520, 324, and 1823 specifically expressed transcripts in the queen, worker, and drone bees, respectively. Furthermore, we identified 38,799 alternative splicing (AS) events from 5710 genes, 44,243 alternative polyadenylation (APA) sites from 1649 gene loci, 88,187 simple sequence repeats (SSRs), and 17,387 long noncoding RNAs (lncRNAs). Leveraging these transcripts as references, we identified 6672, 7795, and 6804 differentially expressed transcripts (DETs) in comparisons of queen ovaries vs drone testes, worker ovaries vs drone testes, and worker ovaries vs queen ovaries, respectively. Our research results provide a comprehensive set of reference transcript datasets for Apis cerana , offering important sequence information for further exploration of its gene functions.

This research focused on utilizing banana peel as the primary material for producing mesoporous biomass charcoal through one-step potassium hydroxide activation. Subsequently, the biomass charcoal underwent high-temperature calcination with varying impregnation ratios of KOH : BC for different durations in tubular furnaces set at different temperatures. The resultant biomass charcoal was then subjected to hydrothermal treatment with FeCl 3 ·6H 2 O to produce biochar/iron oxide composites. The adsorption capabilities of these composites towards methylene blue (MB) were examined under various conditions, including pH (ranging from 3 to 12), temperature variations, and initial MB concentrations (ranging from 50 to 400 mg L -1 ). The adsorption behavior aligned with the Langmuir model and demonstrated quasi-secondary kinetics. After five adsorption cycles, the capacity decreased from 618.64 mg g -1 to 497.18 mg g -1 , indicating considerable stability. Notably, Fe 3 O 4 -N-BC exhibited exceptional MB adsorption performance., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Renal cell carcinoma (RCC) is considered a "metabolic disease" characterized by elevated glycolysis in patients with advanced RCC. Tyrosine kinase inhibitor (TKI) therapy is currently an important treatment option for advanced RCC, but drug resistance may develop in some patients. Combining TKI with targeted metabolic therapy may provide a more effective approach for patients with advanced RCC. An analysis of 14 RCC patients (including three needle biopsy samples with TKI resistance) revealed by sing-cell RNA sequencing (scRNA-seq) that glycolysis played a crucial role in poor prognosis and drug resistance in RCC. TCGA-KIRC and glycolysis gene set analysis identified DEPDC1 as a target associated with malignant progression and drug resistance in KIRC. Subsequent experiments demonstrated that DEPDC1 promoted malignant progression and glycolysis of RCC, and knockdown DEPDC1 could reverse TKI resistance in RCC cell lines. Bulk RNA sequencing (RNA-seq) and non-targeted metabolomics sequencing suggested that DEPDC1 may regulate RCC glycolysis via AKT/mTOR/HIF1α pathway, a finding supported by protein-level analysis. Clinical tissue samples from 98 RCC patients demonstrated that DEPDC1 was associated with poor prognosis and predicted RCC metastasis. In conclusion, this multi-omics analysis suggests that DEPDC1 could serve as a novel target for TKI combined with targeted metabolic therapy in advanced RCC patients with TKI resistance., (© 2024. The Author(s).)

Since the early 20th century, China has gradually established a clinical, educational, and research system centered around modern scientific medicine, which has now become the dominant force in China's medical and health system and services, with the construction and development of the Chinese Academy of Medical Sciences and Peking Union Medical College as the most prominent symbol. The scientific medicine in the new era requires close cooperation across multiple disciplines and fields to build a high-quality and efficient medical and health service system. It also involves combining the excellent traditional Chinese culture with Western medicine to explore a unique path of modern scientific medicine with Chinese characteristics.

The aminated sodium lignosulfonate (AELS) was prepared through a Mannich reaction and characterized via FT-IR, TG, SEM and XPS in this study. Subsequently, the adsorption capacity of AELS for methyl blue (MB) was evaluated under various conditions such as pH, adsorbent dosage, contact time, initial concentration and temperature. The adsorption kinetics, isotherms and thermodynamics of AELS for methyl blue were investigated and analyzed. The results were found to closely adhere to the pseudo-second-order kinetic model and Langmuir isotherm model, suggesting a single-molecular-layer adsorption process. Notably, the maximum adsorption capacity of AELS for methyl blue (153.42 mg g -1 ) was achieved under the specified conditions ( T = 298 K, M AELS = 0.01 g, pH = 6, V MB = 25 mL, C 0 = 300 mg L -1 ). The adsorption process was determined to be spontaneous and endothermic. Following five adsorption cycles, the adsorption capacity exhibited a minimal reduction from 118.99 mg g -1 to 114.33 mg g -1 , indicating good stability. This study contributes to the advancement of utilizing natural resources effectively and sustainably.

Cellulose-based carbon (CBC) is widely known for its porous structure and high specific surface area and is liable to adsorb gas molecules and macromolecular pollutants. However, the application of CBC in gas sensing has been little studied. In this paper, a ZnO/CBC heterojunction was formed by means of simple co-precipitation and high-temperature carbonization. As a new ammonia sensor, the prepared ZnO/CBC sensor can detect ammonia that the previous pure ZnO ammonia sensor cannot at room temperature. It has a great gas sensing response, stability, and selectivity to an ammonia concentration of 200 ppm. This study provides a new idea for the design and synthesis of biomass carbon-metal oxide composites.

Honey bees are typical model organisms for the study of caste differentiation, and the juvenile hormone (JH) is a crucial link in the regulatory network of caste differentiation in honey bees. To investigate the mechanism of JH-mediated caste differentiation, we analyzed the effect of the JH response gene AmKr-h1 on this process. We observed that AmKr-h1 expression levels were significantly higher in queen larvae than in worker larvae at the 48 h, 84 h, and 120 h larval stages, and were regulated by JH. Inhibiting AmKr-h1 expression in honey bee larvae using RNAi could lead to the development of larvae toward workers. We also analyzed the transcriptome changes in honey bee larvae after AmKr-h1 RNAi and identified 191 differentially expressed genes (DEGs) and 682 differentially expressed alternative splicing events (DEASEs); of these, many were related to honey bee caste differentiation. Our results indicate that AmKr-h1 regulates caste differentiation in honey bees by acting as a JH-responsive gene.

Objective: To observe the effect of moxibustion on the indicators of autophagy and apoptosis in the synovium of toes of rats with adjuvant-induced arthritis (AA), so as to explore the underlying mechanism of moxibustion in the treatment of rheumatoid arthritis., Methods: Forty-five SD rats were randomly divided into the blank control group, model group, moxibustion group, methotrexate group and rapamycin group, with 9 rats in each group. The rat model of AA was established by injecting Freund's complete adjuvant. Rats in the moxibustion group received moxibustion treatment at "Zusanli" (ST36) and "Guanyuan" (CV4) for 20 min, once a day. The methotrexate group was given methotrexate intragastrically (0.35 mg/kg) twice a week. The rapamycin group was given rapamycin by intraperitoneal injection (1 mg/kg), once every other day. The toe volume of the left hind limb was measured by the toe volume measuring instrument after 3-day modeling and 3-week intervention respectively. The contents of interlukin(IL)-1 and tumor necrosis factor(TNF)-α in serum were detected by ELISA. The autophagosomes of synovial cells of the toe joint were observed under transmission electron microscope. The expressions of mammalian target of rapamycin(mTOR)C1, p-mTORC1, Caspase-3, Fas and FasL in synovial tissue were detected by Western blot., Results: Under transmission electron microscope, the model group showed decreased autophagosomes in synovial tissues, but the moxibustion, methotrexate, and rapamycin groups showed increased autophagosomes. Compared with the blank control group, the toe volume, the contents of IL-1 and TNF-α in serum and the expression of p-mTORC1 protein in synovial tissue were significantly increased ( P <0.01, P <0.001), while the expressions of Caspase-3, Fas and FasL proteins in synovial tissue were significantly decreased ( P <0.05, P <0.01) in the model group. Compared with the model group, the toe volume, the contents of IL-1 and TNF-α in the serum, and expression of p-mTORC1 protein were significantly decreased ( P <0.05, P <0.01, P <0.001) in the moxibustion group and the methotrexate group, while the expression of Caspase-3, Fas and FasL proteins in synovial tissue in the moxibustion group and the methotrexate group, the expression of Caspase-3 in the rapamycin group were significantly increased ( P <0.05)., Conclusion: Moxibustion can improve joint swelling in AA rats and decrease the contents of serum IL-1 and TNF-α. The mechanism may be related to regulating the expressions of p-mTORC1, Caspase-3, Fas and FasL proteins, and promoting autophagy and apoptosis of synovial cells.

The family of Papilionidae (Lepidoptera: Papilionoidea) is a group of butterflies with high ecological and conservation value. The Hengduan Mountains (HMDs) in Southwest China is an important diversity centre for these butterflies. However, the spatial distribution pattern and the climate vulnerability of Papilionidae butterflies in the HDMs remain unknown to date. The lack of such knowledge has already become an obstacle in formulating effective butterfly conservation strategies. The present research compiled a 59-species dataset with 1938 occurrence points. The Maxent model was applied to analyse the spatial pattern of species richness in subfamilies Parnassiinae and Papilioninae, as well as to predict the response under the influence of climate change. The spatial pattern of both subfamilies in the HDMs has obvious elevation prevalence, with Parnassiinae concentrated in the subalpine to alpine areas (2500-5500 m) in western Sichuan, northwestern Yunnan and eastern Tibet, while Papilioninae is concentrated in the low- to medium-elevation areas (1500-3500 m) in the river valleys of western Yunnan and western Sichuan. Under the influence of climate change, both subfamilies would exhibit northward and upward range shifts. The majority of Parnassiinae species would experience drastic habitat contraction, resulting in lower species richness across the HDMs. In contrast, most Papilioninae species would experience habitat expansion, and the species richness would also increase significantly. The findings of this research should provide new insights and a clue for butterfly diversity and climatic vulnerability in southwestern China. Future conservation efforts should be focused on species with habitat contraction, narrow-ranged distribution and endemicity with both in situ and ex situ measures, especially in protected areas. Commercialised collecting targeting these species must also be regulated by future legislation.

The sex of honey bees is decided by a regulatory cascade comprising of csd, fem and Amdsx. In order to further identify other genes involved in sex determination and differentiation of honey bees in the early stages of embryo development, the CRISPR/Cas9 method was used to knock out fem gene in the embryonic stage of diploid western honey bees, and RNA-seq was used to analyze gene expression changes in the embryo after fem knockout. Finally, we found that the bees had undergone gender changes due to fem knockout. A total of 155 differentially expressed genes (DEGs) were obtained, with 48 up-regulated and 107 down-regulated DEGs in the mutant group compared to the control group. Of them, many genes are related to sex development or differentiation. In addition, 1502 differentially expressed alternative splicing events (DEASEs) related to 1011 genes, including the main honey bee sex-determining genes csd, tra2, fem, and Amdsx, were identified between the mutant group and control group, indicating that fem regulates alternative splicing of a large number of downstream genes. Our results provide valuable clues for further investigating the molecular mechanism of sex determination and differentiation in honey bees., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Zi Long Wang reports financial support was provided by National Natural Science Foundation (No. 32160134). Zi Long Wang reports financial support was provided by Natural Science Foundation of Jiangxi Province (No. 2018ACB21028)., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: To observe the effect of moxibustion on AMP-activated protein kinase (AMPK)/UNC-51-like kinase 1 (ULK1) signaling pathway in the synovial tissue of toes in rheumatoid arthritis rats, so as to explore the mechanism of mo-xibustion in the treatment of rheumatoid arthritis (RA)., Methods: A total of 45 SD rats were randomly divided into blank, model， moxibustion, methotrexate and rapamycin groups, with 9 rats in each group. RA rat model was established by injection of Freund's complete adjuvant. Moxibustion was applied to "Zusanli" (ST36) and "Guanyuan" (CV4) for 20 min, once a day for 3 weeks. Methotrexate group was given methotrexate (0.35 mg/kg) by gavage, twice a week for 3 weeks. Rapamycin group was intraperitoneally injected with rapamycin (1 mg/kg)，once every other day for 3 weeks. The toe volume of the left hind limb of rats was measured by the toe volume measuring instrument. The content of AMP in toe synovium was detected by ELISA. The expression of AMPK and VPS34 protein in toe synovium was detected by Western blot.The expression of ULK1 and Atg13 mRNA in toe synovium was detected by RT-PCR., Results: Compared with the blank group, the volume of toe in the model group was increased ( P <0.01)，while the content of AMP, the expression of AMPK and VPS34 proteins, the expression of ULK1 and Atg13 mRNAs were significantly decreased( P <0.01).Compared with the model group, the volume of toe in the moxibustion，methotre-xate and rapamycin groups was decreased ( P <0.05); the content of AMP, the expression of AMPK and VPS34 proteins, the expression of ULK1 and Atg13 mRNAs were significantly increased( P <0.05) in the moxibustion group; the content of AMP, the expression of VPS34 protein, the expression of Atg13 mRNA were significantly increased( P <0.05) in the methotrexate group; the expression of AMPK and VPS34 proteins, the expression of ULK1 and Atg13 mRNAs were significantly increased ( P <0.05, P <0.01) in the rapamycin group. Compared with the moxibustion group, the expression of AMPK protein in the methotrexate group and the content of AMP in the rapamycin group were significantly decreased ( P <0.05)., Conclusion: Moxibustion can improve joint swelling in RA rats, and the mechanism may be related to promoting the activity of AMPK/ULK1 signaling pathway.

Objective: To observe the effect of electroacupuncture (EA) of "Zusanli"(ST36) and "Guanyuan"(CV4) on the apoptosis rate of synoviocytes and protein expression of Fas, FasL and Caspase-3 in synovial tissue of adjuvant-induced arthritis (AIA) rats, so as to explore its mechanisms underlying improvement of rheumatoid arthritis （RA）., Methods: A total of 24 rats were randomly divided into normal, model, medication and EA groups, with 6 rats in each group. The AIA model was established by injection of complete Freund's adjuvant (CFA, 0.1 mL) into the left hindlimb paw. The rats in the medication group received intraperitoneal injection of 0.35 mg/kg of methotrexate, twice a week for 4 weeks. The rats in the EA group received EA stimulation of ST36 and CV4 (20 Hz/50 Hz, 1 mA) for 20 min, 6 times a week for 4 weeks. The left hind paw volume was measured using a paw volume meter, and histopathological changes of synovial tissue were observed by light microscope after H.E. staining. The serum contents of tumor necrosis factor-α（TNF-α） and interleukin-1 （IL-1） were measured by ELISA. The apoptosis of synoviocytes was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL), and the expression of apoptosis-associated proteins Fas, FasL and Caspase-3 in synovium were detected by Western blot., Results: Compared with the normal group, the left hind paw volume from day 3 to 24 after administration of CFA, serum IL-1 and TNF-α contents were significantly increased ( P <0.01), while the expressions of Fas, FasL and Caspase-3 proteins and apoptotic rate of synoviocytes were significantly decreased in the model group ( P <0.01). In comparison with the model group, the paw volume from day 17 to 24 after modeling, the serum IL-1 and TNF-α contents were significantly reduced ( P <0.01), while the apoptotic rate of synoviocytes, expressions of Fas protein in both medication and EA groups, Caspase-3 protein in the acupuncture group and FasL protein in the medication group were increased ( P <0.01, P <0.05). Compared with the medication group, the expression of FasL protein was decreased in EA group ( P <0.05). H.E. stain showed obvious hyperplasia of the synovial lining layer, and disordered arrangement of synovial cells, with edema and enlargement in some cells in the model group, which was relatively milder in both medication and EA groups., Conclusion: EA of ST36 and CV4 can promote the apoptosis of synoviocytes and the expressions of Fas and FasL proteins in AIA rats, which may contribute to its role in relieving synovitis through activating Fas/FasL signaling.

Quantum many-body systems away from equilibrium host a rich variety of exotic phenomena that are forbidden by equilibrium thermodynamics. A prominent example is that of discrete time crystals 1-8 , in which time-translational symmetry is spontaneously broken in periodically driven systems. Pioneering experiments have observed signatures of time crystalline phases with trapped ions 9,10 , solid-state spin systems 11-15 , ultracold atoms 16,17 and superconducting qubits 18-20 . Here we report the observation of a distinct type of non-equilibrium state of matter, Floquet symmetry-protected topological phases, which are implemented through digital quantum simulation with an array of programmable superconducting qubits. We observe robust long-lived temporal correlations and subharmonic temporal response for the edge spins over up to 40 driving cycles using a circuit of depth exceeding 240 and acting on 26 qubits. We demonstrate that the subharmonic response is independent of the initial state, and experimentally map out a phase boundary between the Floquet symmetry-protected topological and thermal phases. Our results establish a versatile digital simulation approach to exploring exotic non-equilibrium phases of matter with current noisy intermediate-scale quantum processors 21 ., (© 2022. The Author(s).)

Objective: To observe the effects of electroacupuncture (EA) on autophagosomes, unc-51-like autophage activating kinase 1 (ULK1), Beclin1, and microtubule-associated protein light chain 3 (LC3) expression, and synoviocyte ultrastructure in the synovial tissues of rheumatoid arthritis (RA) rats, and to explore the mechanism of EA in regulating the proliferation of synoviocytes via the autophagy pathway., Methods: The SD rats were randomly divided into a normal group, a model group, a methotrexate (MTX) group, and an EA group, with 6 rats in each group. Following RA modeling with Freund's complete adjuvant, rats in the MTX group were treated with intragastric administration of 0.35 mg/kg MTX, twice a week, for 4 weeks, while those in the EA group received 20-min EA stimulation at "Zusanli" (ST36) and "Guanyuan" (CV4), once per day, for 4 weeks, with an interval of one day between weeks. The rat left hind toe volume was measured using the toe volume measuring instrument. HE staining was conducted for detecting the morphology of rat synovial tissues, followed by the observation of autophagosomes under the transmission electron microscope. The levels of serum interleukin (IL)-1 and tumor necrosis factor (TNF)-α were assayed by ELISA, and the protein expression levels of ULK1, Beclin1, and LC3 were detected by Western blot., Results: Compared with the normal group, the left hind toe volume of the model group increased significantly ( P <0.01), while serum IL-1 and TNF-α ( P <0.01), synovial ULK1, Beclin1, and LC3 protein expression ( P <0.01, P <0.05) up-regulated. HE stain and electron microscope showed obvious synovial hyperplasia, and doublemembrane autophagosomes scattering in the synoviocytes. The comparison with the model group showed that MTX and EA remarkably decreased the left hind toe volume ( P <0.01), serum IL-1 and TNF-α ( P <0.01), down-regulated the protein expression levels of ULK1 and LC3 in synovial tissues ( P <0.05, P <0.01), and inhibited the synovial hyperplasia, with no obvious autophagosomes observed in the synoviocytes. The protein expression of ULK1 in the EA group was significantly lower than that in the MTX group ( P <0.01)., Conclusion: EA alleviates the joint swelling and synoviocyte injury of RA rats possibly by regulating the expression of ULK1, LC3, and Beclin1 and inhibiting the synoviocyte autophagy and proliferation.

A novel chromium(VI)-based compound, [(CH 3 CH 2 ) 3 N(CH 2 Cl)][CrO 3 Cl] (1), undergoes a high-temperature phase transition at around 340.9 K, accompanied by an ultra-large entropy change of 63.49 J mol -1 K -1 . Compound 1 exhibits a moderate ferroelectric polarization of 0.48 μC cm -2 and a remarkable CD signal. Strikingly, 1 occupies a narrow band gap of 2.22 eV, which is chiefly attributed to the inorganic [CrO 3 Cl] - tetrahedron. It is believed that these findings will contribute to an alternative pathway for the design of multifunctional ferroelectric materials, whose potential applications will be in semiconductors, energy storage, etc.

Chicken colibacillosis is caused by avian pathogenic Escherichia coli (APEC), and results in huge economic losses to the poultry industry. With the investigation of the gut-lung axis, more studies have demonstrated the important role of gut microbiota in lung inflammation. The precise role of the gut microbiota in chickens-associated colibacillosis, however, is unknown. Thus, this study assessed the function of the gut microbiota in the chicken defense against APEC infection. Chicken gut microbiota was depleted by drinking water with a mixture of antibiotics (Abx), and subsequently, a model of colibacillosis was established by the intranasal perfusion of APEC. The results showed that gut microbiota protects the chicken challenge by APEC from aggravated lung histopathologic injury, up-regulated pro-inflammatory cytokine production, and increased bacterial load in lung tissues compared with controls. In addition, the air-blood barrier permeability was significantly increased in gut microbiota-depleted chickens compared to the control chickens after challenge with APEC. Furthermore, feeding acetate significantly inhibited the lung inflammatory response and the reduced air-blood permeability induced by APEC infection. The expression of free fatty acid receptor 2 (FFAR2), a receptor for acetate, was also increased in the lung after treatment with acetate. In conclusion, depletion of the gut microbiota resulted in increased susceptibility of chickens to APEC challenge, and gut microbiota derived acetate acted as a protective mediator during the APEC challenge. Novel therapeutic targets that focus on the gut microbiota may be effective in controlling colibacillosis in poultry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Workplace climate is a great significant element that has an impact on nurses' behavior and practice; moreover, nurses' service behavior contributes to the patients' satisfaction and subsequently to the long-term success of hospitals. Few studies explore how different types of organizational ethical climate encourage nurses to engage in both in-role and extra-role service behaviors, especially in comparing the influencing process between public and private hospitals. This study aimed to compare the relationship between the five types of ethical climate and nurses' in-role and extra-role service behaviors in public and private hospitals., Methods: This study conducted a cross-sectional survey on 559 nurses from China in May 2019. The questionnaire was distributed to nurses by sending a web link via the mobile phone application WeChat through snowball sampling methods. All participants were investigated using the Ethical Climate Scale and Service Behavior Questionnaire. SPSS 22.0 was used for correlation analysis, t-test, and analysis of variance test, and Mplus 7.4 was used for group comparison (p < .05)., Results: The law and code climate has a much greater influence on nurses' in-role service behavior in private hospitals than on that in public hospitals (β = - 0.277; CI 95 % = [-0.452, - 0.075]; p < .01), and the instrumental climate has a stronger influence on nurses' extra-role service behavior private hospitals than on that in public hospitals (β = - 0.352; CI 95 % = [-0.651, - 0.056]; p < .05). Meanwhile, the rules climate has a greater effect on nurses' extra-role service behavior in public hospitals than it does in private hospitals (β = 0.397; CI 95 % = [0.120, 0.651]; p < .01)., Conclusions: As the relationship between the five types of ethical climate and nurses' in-role and extra-role service behaviors in public and private hospitals were different, the strategies used to foster and enhance the types of ethical climate are various from public to private hospitals. The caring and instrumental climate are the key to promote extra-role service behavior for nurses in private hospitals. And the independent climate has a great effect on extra-role service behaviors for nurses in public hospitals., (© 2021. The Author(s).)

The well-studied star compound, CH3NH3PbI3, has attracted plenty of attention because of its remarkable optical and electrical properties. Consequently, new switching multifunctional hybrid compounds can be widely used in many fields such as solar cells, light-emitting diodes, optical data storage and so on. Therefore, switching multifunctional hybrid compounds with dielectric and semiconducting properties simultaneously will also find roles in the next generation of optoelectronic coupling materials. In fact, discovering an effective method to synthesize (multi)functional hybrid materials remains a pressing challenge. Thanks to the "quasi-spherical theory" proposed by Xiong et al., we used 7-azabicyclo[2.2.1]heptane as the quasi-spherical cation to construct molecule-based crystalline materials that exhibit responsive properties. Then, we tried to exploit the knowledge of crystal engineering and coordination chemistry to explain (multi)functional molecular materials. A layered organic-inorganic hybrid compound, (C6H12N)2Pb(NO3)4 (1), was grown and its dielectric switching property and semiconducting behaviour were investigated. Insights from differential scanning calorimetry measurements, variable-temperature X-ray structural studies, and dielectric spectroscopy revealed the origin of the phase transition, which is related to the motion of the organic ammonium and inorganic framework in solid-state crystals. Furthermore, 1 is also a wide bandgap semiconductor with an optical bandgap of 3.53 eV. The realization of switching and semiconducting properties simultaneously in layered Pb-based perovskites has a great significance toward research into hybrid compounds and the development of dielectric-optoelectronic integrated materials.

As a major branch of hybrid perovskites, two-dimensional (2D) hybrid double perovskites are expected to be ideal systems for exploring novel ferroelectric properties, because they can accommodate a variety of organic cations and allow diverse combinations of different metal elements. However, no 2D hybrid double perovskite ferroelectric has been reported since the discovery of halide double perovskites in the 1930s. Based on trivalent rare-earth ions and chiral organic cations, we have designed a new family of 2D rare-earth double perovskite ferroelectrics, A 4 M I M III (NO 3 ) 8 , where A is the organic cation, M I is the alkaline metal or ammonium ion, and M III is the rare-earth ion. This is the first time that ferroelectricity is realized in 2D hybrid double perovskite systems. These ferroelectrics have achieved high-temperature ferroelectricity and photoluminescent properties. By varying the rare-earth ion, variable photoluminescent properties can be achieved. The results reveal that the 2D rare-earth double perovskite systems provide a promising platform for achieving multifunctional ferroelectricity.

Substitution of A-site and/or X-site ions of ABX 3 -type perovskites with organic groups can give rise to hybrid perovskites, many of which display intriguing properties beyond their parent compounds. However, this method cannot be extended effectively to hybrid antiperovskites. Now, the design of hybrid antiperovskites under the guidance of the concept of Goldschmidt's tolerance factor is presented. Spherical anions were chosen for the A and B sites and spherical organic cations for the X site, and seven hybrid antiperovskites were obtained, including (F 3 (H 2 O) x )(AlF 6 )(H 2 dabco) 3 , ((Co(CN) 6 )(H 2 O) 5 )(MF 6 )(H 2 dabco) 3 (M=Al 3+ , Cr 3+ , or In 3+ ), (Co(CN) 6 )(MF 6 )(H 2 pip) 3 (M=Al 3+ or Cr 3+ ), and (SbI 6 )(AlF 6 )(H 2 dabco) 3 . These new structures reveal that all ions at A, B, and X sites of inorganic antiperovskites can be replaced by molecular ions to form hybrid antiperovskites. This work will lead to the synthesis of a large family of hybrid antiperovskites., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Strongly long-range interacting quantum systems-those with interactions decaying as a power law 1/ r α in the distance r on a D -dimensional lattice for α ⩽ D -have received significant interest in recent years. They are present in leading experimental platforms for quantum computation and simulation, as well as in theoretical models of quantum-information scrambling and fast entanglement creation. Since no notion of locality is expected in such systems, a general understanding of their dynamics is lacking. In a step towards rectifying this problem, we prove two Lieb-Robinson-type bounds that constrain the time for signaling and scrambling in strongly long-range interacting systems, for which no tight bounds were previously known. Our first bound applies to systems mappable to free-particle Hamiltonians with long-range hopping, and is saturable for α ⩽ D /2. Our second bound pertains to generic long-range interacting spin Hamiltonians and gives a tight lower bound for the signaling time to extensive subsets of the system for all α < D . This many-site signaling time lower bounds the scrambling time in strongly long-range interacting systems.

Bhutanitis thaidina is an endemic, rare, and protected swallowtail in China. Deforestation, habitat fragmentation, illegal commercialised capture, and exploitation of larval food plants are believed to be the four major causes of population decline of B. thaidina in the recent decade. However, little attention was paid to the impact of climate change. This study used ecological niche factor analysis and species distribution model to analyse the current suitable areas for B. thaidina with BioClim variables as well as its future suitable areas under four future climate scenarios (represented by four Representative Concentration Pathways: RCP2.6, RCP4.5, RCP6.0, and RCP8.5). Statistical analysis was carried out to compare the possible area and altitude changes to the distribution of B. thaidina under changing climate. Our analyses showed that the suitable areas for B. thaidina are fragmented under the current climate, with four suitable centres in northwestern Yunnan, northeastern Yunnan and northwestern Guizhou, the western margin of Sichuan Basin, and Qinling mountains. Apart from further habitat fragmentation under climate change, slight range expansion (average 6.0-8.9%) was detected under the RCP2.6 and RCP4.5 scenarios, while more range contraction (average 1.3-26.9%) was detected under the RCP6.0 and RCP8.5 scenarios, with the two southern suitable centres suffering most. Also, a tendency of contraction (2,500-3,500 m) and upslope shift (~600 m) in suitable altitude range were detected. The findings of this study supported the climate-vulnerable hypothesis of B. thaidina, especially under future climate like the RCP6.0 and RCP8.5 scenarios, in terms of contraction in suitable areas and altitude ranges. Conservation priority should be given to northwestern Yunnan, northeastern Yunnan, and northwestern Guizhou to alleviate the stress of massive habitat loss and extinction. Refugial areas should be established in all four suitable centres to maintain genetic diversity of B. thaidina in China.

The study of quantum phase transitions requires the preparation of a many-body system near its ground state, a challenging task for many experimental systems. The measurement of quench dynamics, on the other hand, is now a routine practice in most cold atom platforms. Here we show that quintessential ingredients of quantum phase transitions can be probed directly with quench dynamics in integrable and nearly integrable systems. As a paradigmatic example, we study global quench dynamics in a transverse-field Ising model with either short-range or long-range interactions. When the model is integrable, we discover a new dynamical critical point with a nonanalytic signature in the short-range correlators. The location of the dynamical critical point matches that of the quantum critical point and can be identified using a finite-time scaling method. We extend this scaling picture to systems near integrability and demonstrate the continued existence of a dynamical critical point detectable at prethermal timescales. We quantify the difference in the locations of the dynamical and quantum critical points away from (but near) integrability. Thus, we demonstrate that this method can be used to approximately locate the quantum critical point near integrability. The scaling method is also relevant to experiments with finite time and system size, and our predictions are testable in near-term experiments with trapped ions and Rydberg atoms.

Aim: To explore the relationship between ethical climate (EC) and nurses' service behaviours (SB) and examine the moderating effect of nurses' employment type., Background: As most public hospitals in China implement the "dual-track system" of nurses' employment, the two different types of nurses, contract-employed nurses and state-employed nurses, receive the different pay for the same work, which results in they providing different SB. It has become critical for hospital administrators and nursing managers to understand better the state of two groups of nurses and to find an effective method to improve the service level of the nursing workforce., Design: Stepwise multiple regression analyses of survey data collected in June and July 2017 from Chinese nurses employed in three tertiary hospitals., Methods: Chinese nurses (298 of 350 [85.1%]) were interviewed using the Ethical Climate Scale and Nurses' Service Behaviour Scale. Data were analysed statistically using descriptive statistics, confirmatory factor analysis, correlation coefficients (Pearson), two-tailed t-test and stepwise multiple regression analyses were conducted to test the proposed hypotheses. Data were analysed using SPSS and AMOS., Results: There were statistically significant correlations between EC and nurses' extra-role service behaviour (ERSB) and overall service behaviour and nurses' employment type moderated the proposed relationships., Conclusion: Healthcare institutions should pay more attention to cultivate EC and implement new incentive mechanism to better stimulate nurses to provide ERSB., (© 2019 John Wiley & Sons Ltd.)

We study the nonequilibrium dynamics of Abelian anyons in a one-dimensional system. We find that the interplay of anyonic statistics and interactions gives rise to spatially asymmetric particle transport together with a novel dynamical symmetry that depends on the anyonic statistical angle and the sign of interactions. Moreover, we show that anyonic statistics induces asymmetric spreading of quantum information, characterized by asymmetric light cones of out-of-time-ordered correlators. Such asymmetric dynamics is in sharp contrast to the dynamics of conventional fermions or bosons, where both the transport and information dynamics are spatially symmetric. We further discuss experiments with cold atoms where the predicted phenomena can be observed using state-of-the-art technologies. Our results pave the way toward experimentally probing anyonic statistics through nonequilibrium dynamics.

A quantum simulator is a type of quantum computer that controls the interactions between quantum bits (or qubits) in a way that can be mapped to certain quantum many-body problems. As it becomes possible to exert more control over larger numbers of qubits, such simulators will be able to tackle a wider range of problems, such as materials design and molecular modelling, with the ultimate limit being a universal quantum computer that can solve general classes of hard problems. Here we use a quantum simulator composed of up to 53 qubits to study non-equilibrium dynamics in the transverse-field Ising model with long-range interactions. We observe a dynamical phase transition after a sudden change of the Hamiltonian, in a regime in which conventional statistical mechanics does not apply. The qubits are represented by the spins of trapped ions, which can be prepared in various initial pure states. We apply a global long-range Ising interaction with controllable strength and range, and measure each individual qubit with an efficiency of nearly 99 per cent. Such high efficiency means that arbitrary many-body correlations between qubits can be measured in a single shot, enabling the dynamical phase transition to be probed directly and revealing computationally intractable features that rely on the long-range interactions and high connectivity between qubits.

In short-range interacting systems, the speed at which entanglement can be established between two separated points is limited by a constant Lieb-Robinson velocity. Long-range interacting systems are capable of faster entanglement generation, but the degree of the speedup possible is an open question. In this Letter, we present a protocol capable of transferring a quantum state across a distance L in d dimensions using long-range interactions with a strength bounded by 1/r^{α}. If α

Although statistical mechanics describes thermal equilibrium states, these states may or may not emerge dynamically for a subsystem of an isolated quantum many-body system. For instance, quantum systems that are near-integrable usually fail to thermalize in an experimentally realistic time scale, and instead relax to quasi-stationary prethermal states that can be described by statistical mechanics, when approximately conserved quantities are included in a generalized Gibbs ensemble (GGE). We experimentally study the relaxation dynamics of a chain of up to 22 spins evolving under a long-range transverse-field Ising Hamiltonian following a sudden quench. For sufficiently long-range interactions, the system relaxes to a new type of prethermal state that retains a strong memory of the initial conditions. However, the prethermal state in this case cannot be described by a standard GGE; it rather arises from an emergent double-well potential felt by the spin excitations. This result shows that prethermalization occurs in a broader context than previously thought, and reveals new challenges for a generic understanding of the thermalization of quantum systems, particularly in the presence of long-range interactions.

We prove that the entanglement entropy of any state evolved under an arbitrary 1/r^{α} long-range-interacting D-dimensional lattice spin Hamiltonian cannot change faster than a rate proportional to the boundary area for any α>D+1. We also prove that for any α>2D+2, the ground state of such a Hamiltonian satisfies the entanglement area law if it can be transformed along a gapped adiabatic path into a ground state known to satisfy the area law. These results significantly generalize their existing counterparts for short-range interacting systems, and are useful for identifying dynamical phase transitions and quantum phase transitions in the presence of long-range interactions.

Continuous symmetry breaking (CSB) in low-dimensional systems, forbidden by the Mermin-Wagner theorem for short-range interactions, may take place in the presence of slowly decaying long-range interactions. Nevertheless, there is no stringent bound on how slowly interactions should decay to give rise to CSB in 1D quantum systems at zero temperature. Here, we study a long-range interacting spin chain with U(1) symmetry and power-law interactions V(r)∼1/r^{α}. Using a number of analytical and numerical techniques, we find CSB for α smaller than a critical exponent α&#95;{c}(≤3) that depends on the microscopic parameters of the model. Furthermore, the transition from the gapless XY phase to the gapless CSB phase is mediated by the breaking of conformal and Lorentz symmetries due to long-range interactions, and is described by a universality class akin to, but distinct from, the Berezinskii-Kosterlitz-Thouless transition. Signatures of the CSB phase should be accessible in existing trapped-ion experiments.

Lieb and Robinson provided bounds on how fast bipartite connected correlations can arise in systems with only short-range interactions. We generalize Lieb-Robinson bounds on bipartite connected correlators to multipartite connected correlators. The bounds imply that an n -partite connected correlator can reach unit value in constant time. Remarkably, the bounds also allow for an n -partite connected correlator to reach a value that is exponentially large with system size in constant time, a feature which stands in contrast to bipartite connected correlations. We provide explicit examples of such systems.

A core-shell structured chitosan (CS)-based gene vector with a sustainable gene transfection effect was designed and successfully prepared in this study. The pEGFP was first combined with the thiolated and N-alkylated chitosan (TACS). Then, hydroxybutyl chitosan grafted with poly(ethylene glycol) (EG-HBC) was coated on the pEGFP-loaded TACS particles. The prepared pEGFP-loaded TACS@EG-HBC particles have a size of about 200 nm and little cytotoxicity. The in vitro and in vivo gene transfection experiments indicate that the pEGFP-loaded TACS@EG-HBC particles possess a better sustainable gene transfection capacity and a high transfection efficiency, which should be attributed to the biodegradation of the CS-based shell, the thiolation and N-alkylation modification on CS cores, and the grafted PEG chains with better biocompatibility. The in vivo gene expression of the loaded pEGFP can persist up to 60 days. This novel gene vector has a theoretical and practical significance for gene therapy with sustained transfection effect.

Motivated directly by recent trapped-ion quantum simulation experiments, we carry out a comprehensive study of the phase diagram of a spin-1 chain with XXZ-type interactions that decay as 1/ r α , using a combination of finite and infinite-size DMRG calculations, spin-wave analysis, and field theory. In the absence of long-range interactions, varying the spin-coupling anisotropy leads to four distinct and well-studied phases: a ferromagnetic Ising phase, a disordered XY phase, a topological Haldane phase, and an antiferromagnetic Ising phase. If long-range interactions are antiferromagnetic and thus frustrated, we find primarily a quantitative change of the phase boundaries. On the other hand, ferromagnetic (nonfrustrated) long-range interactions qualitatively impact the entire phase diagram. Importantly, for α ≲ 3 long-range interactions destroy the Haldane phase, break the conformal symmetry of the XY phase, give rise to a new phase that spontaneously breaks a U (1) continuous symmetry, and introduce a possibly exotic tricritical point with no direct parallel in short-range interacting spin chains. Importantly, we show that the main signatures of all five phases found could be observed experimentally in the near future.

Long-range quantum lattice systems often exhibit drastically different behavior than their short-range counterparts. In particular, because they do not satisfy the conditions for the Lieb-Robinson theorem, they need not have an emergent relativistic structure in the form of a light cone. Adopting a field-theoretic approach, we study the one-dimensional transverse-field Ising model with long-range interactions, and a fermionic model with long-range hopping and pairing terms, explore their critical and near-critical behavior, and characterize their response to local perturbations. We deduce the dynamic critical exponent, up to the two-loop order within the renormalization group theory, which we then use to characterize the emergent causal behavior. We show that beyond a critical value of the power-law exponent of the long-range couplings, the dynamics effectively becomes relativistic. Various other critical exponents describing correlations in the ground state, as well as deviations from a linear causal cone, are deduced for a wide range of the power-law exponent.

Topological phases of matter are primarily studied in systems with short-range interactions. In nature, however, nonrelativistic quantum systems often exhibit long-range interactions. Under what conditions topological phases survive such interactions, and how they are modified when they do, is largely unknown. By studying the symmetry-protected topological phase of an antiferromagnetic spin-1 chain with 1/ r α interactions, we show that two very different outcomes are possible, depending on whether or not the interactions are frustrated. While unfrustrated long-range interactions can destroy the topological phase for α ≲ 3, the topological phase survives frustrated interactions for all α > 0. Our conclusions are based on strikingly consistent results from large-scale matrix-product-state simulations and effective-field-theory calculations, and we expect them to hold for more general interacting spin systems. The models we study can be naturally realized in trapped-ion quantum simulators, opening the prospect for experimental investigation of the issues confronted here.

This study aimed to investigate the protective effects of delayed morphine preconditioning on myocardial ischemia-reperfusion injury. We randomly divided 30 rabbits into three groups with 10 rab-bits in each group as follows: sham operation group (C group), isch-emia-reperfusion group (I/R group), and morphine pretreatment group (M group). Rabbits in C Group received left coronary without blocking for 160 min. The left descending artery of rabbits in the I/R group was blocked for 40 min and reperfused for 120 min. Rabbits in the M group received intravenous administration of 1.0 mg/kg morphine; after 24 h, rabbits in this group received the same treatment as that administered to the I/R group. We determined tumor necrosis factor alpha (TNF-α) levels in blood samples from the internal carotid artery of rabbits in each group 20 min before occlusion of the left descending coronary artery, 20 and 40 min after occlusion of the left descending coronary artery, and 1 and 2 h after myocardial reperfusion. After 120 min of reperfusion, immunoblotting was used to measure the activity levels of myocardial p38 mitogen-activated protein kinase (MAPK); in addition, the infarct size was measured. Compared to the I/R group, the M group showed a significant decrease in TNF-α levels, p38 MAPK activity, and the myocardial infarct size (I/R group 37.8% ± 1.7% vs 21.5% ± 2.4%; P < 0.05). Thus, morphine preconditioning in the delayed phase may exert protective effects on myocardial I/R injury by inhibiting myocar-dial p38 MAPK activity and decreasing TNF-α production.

Objective: To evaluate the efficacy and safety of Flos Abelmoschus manihot (Malvaceae) on type 2 diabetic nephropathy (DN)., Methods: The Cochrane Library, PubMed/MEDLINE, Excerpta Medical Database, Chinese electronic literature databases, and the references of relevant articles were searched in March 2012 for randomized controlled trials (RCTs) that reported the effects of Flos A. manihot on type 2 DN patients with overt but subnephrotic-range proteinuria (500-3,500 mg/24 h). The quality of trials was evaluated using the Cochrane-recommended method. The results were summarized as risk ratios (RRs) for dichotomous outcomes or mean differences (MDs) for continuous outcomes., Results: Seven trials (531 patients) were included. Flos A. manihot significantly decreased proteinuria [MD -317.32 mg/24 h, 95% confidence interval (CI) [-470.48, -164.17],P<0.01]. After excluding a trial that only included patients with well-preserved renal function, Flos A. manihot was associated with a significant decrease in serum creatinine (MD -11.99 μmol/L, 95% CI [-16.95, -7.04],P<0.01). Serious adverse events were not observed. The most common adverse event was mild to moderate gastrointestinal discomfort; however, patients receiving this herb did not have an increased risk for tolerated gastrointestinal discomfort (RR 1.48, 95% CI [0.39, 5.68],P=0.57)., Conclusions: Flos A. manihot may be considered as an important adjunctive therapy with the first-line and indispensable therapeutic strategies for type 2 DN. High-quality RCTs are urgently needed to confirm the effect of Flos A. manihot on definite endpoints such as end-stage renal disease.

In nonrelativistic quantum theories with short-range Hamiltonians, a velocity v can be chosen such that the influence of any local perturbation is approximately confined to within a distance r until a time t∼r/v, thereby defining a linear light cone and giving rise to an emergent notion of locality. In systems with power-law (1/r^{α}) interactions, when α exceeds the dimension D, an analogous bound confines influences to within a distance r only until a time t∼(α/v)logr, suggesting that the velocity, as calculated from the slope of the light cone, may grow exponentially in time. We rule out this possibility; light cones of power-law interacting systems are bounded by a polynomial for α>2D and become linear as α→∞. Our results impose strong new constraints on the growth of correlations and the production of entangled states in a variety of rapidly emerging, long-range interacting atomic, molecular, and optical systems.

Motivated by recent experiments with ultracold matter, we derive a new bound on the propagation of information in D-dimensional lattice models exhibiting 1/r^{α} interactions with α>D. The bound contains two terms: One accounts for the short-ranged part of the interactions, giving rise to a bounded velocity and reflecting the persistence of locality out to intermediate distances, whereas the other contributes a power-law decay at longer distances. We demonstrate that these two contributions not only bound but, except at long times, qualitatively reproduce the short- and long-distance dynamical behavior following a local quench in an XY chain and a transverse-field Ising chain. In addition to describing dynamics in numerous intractable long-range interacting lattice models, our results can be experimentally verified in a variety of ultracold-atomic and solid-state systems.

The maximum speed with which information can propagate in a quantum many-body system directly affects how quickly disparate parts of the system can become correlated and how difficult the system will be to describe numerically. For systems with only short-range interactions, Lieb and Robinson derived a constant-velocity bound that limits correlations to within a linear effective 'light cone'. However, little is known about the propagation speed in systems with long-range interactions, because analytic solutions rarely exist and because the best long-range bound is too loose to accurately describe the relevant dynamical timescales for any known spin model. Here we apply a variable-range Ising spin chain Hamiltonian and a variable-range XY spin chain Hamiltonian to a far-from-equilibrium quantum many-body system and observe its time evolution. For several different interaction ranges, we determine the spatial and time-dependent correlations, extract the shape of the light cone and measure the velocity with which correlations propagate through the system. This work opens the possibility for studying a wide range of many-body dynamics in quantum systems that are otherwise intractable.

We demonstrate entangling quantum gates within a chain of five trapped ion qubits by optimally shaping optical fields that couple to multiple collective modes of motion. We individually address qubits with segmented optical pulses to construct multipartite entangled states in a programmable way. This approach enables high-fidelity gates that can be scaled to larger qubit registers for quantum computation and simulation.

Photonic quantum simulators are promising candidates for providing insight into other small- to medium-sized quantum systems. Recent experiments have shown that photonic quantum systems have the advantage to exploit quantum interference for the quantum simulation of the ground state of Heisenberg spin systems. Here we experimentally characterize this quantum interference at a tuneable beam splitter and further investigate the measurement-induced interactions of a simulated four-spin system by comparing the entanglement dynamics using pairwise concurrence. We also study theoretically a four-site square lattice with next-nearest neighbor interactions and a six-site checkerboard lattice, which might be in reach of current technology.

Spontaneous symmetry breaking can lead to the formation of time crystals, as well as spatial crystals. Here we propose a space-time crystal of trapped ions and a method to realize it experimentally by confining ions in a ring-shaped trapping potential with a static magnetic field. The ions spontaneously form a spatial ring crystal due to Coulomb repulsion. This ion crystal can rotate persistently at the lowest quantum energy state in magnetic fields with fractional fluxes. The persistent rotation of trapped ions produces the temporal order, leading to the formation of a space-time crystal. We show that these space-time crystals are robust for direct experimental observation. We also study the effects of finite temperatures on the persistent rotation. The proposed space-time crystals of trapped ions provide a new dimension for exploring many-body physics and emerging properties of matter.

We propose and analyze a new approach for quantum state transfer between remote spin qubits. Specifically, we demonstrate that coherent quantum coupling between remote qubits can be achieved via certain classes of random, unpolarized (infinite temperature) spin chains. Our method is robust to coupling-strength disorder and does not require manipulation or control over individual spins. In principle, it can be used to attain perfect state transfer over an arbitrarily long range via purely Hamiltonian evolution and may be particularly applicable in a solid-state quantum information processor. As an example, we demonstrate that it can be used to attain strong coherent coupling between nitrogen-vacancy centers separated by micrometer distances at room temperature. Realistic imperfections and decoherence effects are analyzed.