Digital quantum simulation of Floquet symmetry-protected topological phases.

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 crystals1-8, in which time-translational symmetry is spontaneously broken in periodically driven systems. Pioneering experiments have observed signatures of time crystalline phases with trapped ions9,10, solid-state spin systems11-15, ultracold atoms16,17 and superconducting qubits18-20. 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 processors21.

Circ_016719 plays a critical role in neuron cell apoptosis induced by I/R via targeting miR-29c/Map2k6.

BACKGROUND: Stroke is a leading cause of mortality worldwide. Rac-MAPK kinase 6 (Map2k6) plays important roles in cell proliferation and apoptosis. However, the role played by Map2k6 in stroke injury and the underlying mechanism of action remain unknown. METHODS: Mice received cerebral ischemia/reperfusion (I/R) injuries by transient middle cerebral artery occlusion. HT22 cells were subjected to oxygen glucose deprivation and reoxygenation (OGD/R) to simulate an I/R injury. Subsequently, the levels of circ_016719, miR-29c and Map2k6 expression were determined, and their interactions were examined by luciferase assays. Circ_016719 knockdown, miR-29c inhibition or Map2k6 overexpression was induced in HT22 cells; after which, the cells were examined for their viability, apoptosis, autophagy and proliferation, as well their levels of Map2k6, p38, p53, LC3B-I, LC3B-II, Beclin 1, and p62 expression. RESULTS: Significantly increased levels of circ_016719 and Map2k6, and decreased levels of miR-29c were observed in both in vivo and in vitro I/R injury models. In HT22 cells, circ_016719 knockdown significantly increased miR-29c expression and cell proliferation, but decreased Map2k6 expression and cell apoptosis. Additionally, significant increases in LC3B-I and p62 levels and decreased LC3B-II levels were observed, indicating that circ_016719 knockdown had significantly inhibited autophagy. Furthermore, additional inhibition of miR-29c markedly suppressed the effects of circ_016719 knockdown; however, that suppression was significantly attenuated by Map2k6 overexpression. Additionally, Map2k6 was identified as a direct target of miR-29c, which in turn, might be sponged by circ_016719. CONCLUSIONS: Our results suggest that circ_016719 directly targets miR-29c, and thereby regulates the expression and functions of Map2k6, which significantly contributes to the pro-apoptotic role of circ_016719.

Preparation and identification of polyclonal antibody against human cytomegalovirus encoding protein UL23.

Human cytomegalovirus (HCMV), a member of the human herpesvirus family, is a common opportunistic virus causing severe ailments and deaths in people with immature or compromised immune systems. UL23 is a virion protein found in the tegument and is expressed in the cytoplasm in HCMV infected cells. However, UL23 is dispensable for viral replication in cultured cells and little is currently known about its function. In order to further study of UL23, polyclonal antibody of UL23 was prepared. UL23 gene fragment was cloned from HCMV Towne by PCR and ligated into pET28a (+). The recombinant plasmid pET28a (+)-UL23 was transformed into E.coli BL21(DE3) to induce expression of the target protein. Then we efficiently purified the recombinant protein affinity chromatography under unique denaturation conditions. Recombinant UL23 protein was used as immunogen to inoculate New Zealand white rabbits and the sera was collected after the fourth immunization. UL23 Polyclonal antibody was purified from antisera using CNBr-activated Sepharose 4 beads. Our UL23 Polyclonal antibody showed specific reaction with UL23 in ELISA, Western-blot and immunofluorescence. More importantly, UL23 Polyclonal antibody could specifically recognize UL23 protein in HCMV infected cells, which laid a foundation for further study of HCMV UL23.

Contrast-enhanced transcranial Doppler for the detection of right-to-left shunt: A new provocation method with a syringe-modified Valsalva maneuver.

BACKGROUND: Contrast-enhanced transcranial Doppler (cTCD) study has been established as one of the most common investigations for detecting right-to-left shunt (RLS). Although the conventional Valsalva maneuver (c-VM) has been used to increase the sensitivity of cTCD for RLS, efforts are still needed to improve the detection rate further. We proposed a new provocation method with a syringe-modified Valsalva maneuver (sm-VM) during cTCD and compared the efficacy of this strategy with cTCD measured at resting and with the provocation of c-VM. METHODS: Consecutive patients with suspicion of RLS who underwent cTCD in our institution between September 27, 2021, and April 1, 2022, were included in this study. Examination of cTCD was performed separately at the resting state and provoked with c-VM and sm-VM. The overall proportion of patients with RLS and their distribution with different RLS grades were compared. RESULTS: A total of 389 patients (mean age: 49.37 years, male: 52.2%) were included in this study. The positive rate for RLS was significantly higher for cTCD detected with sm-VM than those detected at resting state and with c-VM (46.8% vs. 21.6% and 34.2%, all p < .05). Besides, cTCD detected with sm-VM was also associated with a higher proportion of patients with grade III RLS than those detected at resting state and with c-VM (11.3% vs. 1.8% and 0%, all p < .05). CONCLUSIONS: Compared to cTCD detected at resting state and with c-VM, cTCD with sm-VM could further increase the positive detection rate of RLS.

Physicochemical and Structural Characterization of Alkali-Treated Biopolymer Sphingan WL Gum from Marine Sphingomonas sp. WG.

Sphingan WL gum (WL), a kind of exopolysaccharide, is produced by Sphingomonas sp. WG, which was screened from sea mud samples of Jiaozhou Bay by our group. The solubility of WL was investigated in this work. First, 1 mg/mL of WL solution was stirred at room temperature for at least 2 h to obtain a uniform opaque liquid, and further the solution became clear with the increased NaOH and stirring time. Subsequently, the structural features, solubility, and rheological properties of WL before and after alkali treatment were compared systematically. FTIR, NMR, and zeta potential results indicate that the alkali causes acetyl group hydrolysis and carboxyl group deprotonation. XRD, DLS, GPC, and AFM results suggest that the alkali destroys the ordered arrangement and inter- and intrachain entanglement of polysaccharide chains. In the same case, 0.9 M NaOH-treated WL presents better solubility (stirring for 15 min to obtain a clarified solution) but, unsurprisingly, worsens rheological properties. All results demonstrated that the good solubility and transparency of alkali-treated WL will help promote its postmodification and application.

Citric acid crosslinked sphingan WL gum hydrogel films supported ciprofloxacin for potential wound dressing application.

Sphingan WL gum (WL), a kind of exopolysaccharides, is produced by Sphingomonas sp. WG. In this study, citric acid (CA) crosslinked WL hydrogel films were firstly developed for potential wound dressing application. ATR-FTIR and TG results suggested the occurrence of esterification crosslinking. SEM analysis showed that this aided covalent crosslinking could prevent their porous structures from collapsing when swelling. Due to the deprotonation of carboxyl groups, the water absorption capacity of WL-CA hydrogel films increased with the increase of pH (maximum swelling ratio = 38 g/g). The covalent crosslinked swollen WL-CA hydrogels exhibited certain hydrolytic stability, high porosity (>60%), moderate tissue adhesion, and good rheological property (G' > G″, G' up to 2 kPa). WL-CA-CIP hydrogel films loaded with antibiotic ciprofloxacin (CIP) showed sustained drug release properties, long-lasting antibacterial activity, and superior biocompatibility. All the results indicated that WL-based hydrogels were potential candidates for wound dressing applications.

Observing the quantum topology of light.

Topological photonics provides a powerful platform to explore topological physics beyond traditional electronic materials and shows promising applications in light transport and lasers. Classical degrees of freedom are routinely used to construct topological light modes in real or synthetic dimensions. Beyond the classical topology, the inherent quantum nature of light provides a wealth of fundamentally distinct topological states. Here we implement experiments on topological states of quantized light in a superconducting circuit, with which one- and two-dimensional Fock-state lattices are constructed. We realize rich topological physics including topological zero-energy states of the Su-Schrieffer-Heeger model, strain-induced pseudo-Landau levels, valley Hall effect, and Haldane chiral edge currents. Our study extends the topological states of light to the quantum regime, bridging topological phases of condensed-matter physics with circuit quantum electrodynamics, and offers a freedom in controlling the quantum states of multiple resonators.

Experimental quantum adversarial learning with programmable superconducting qubits.

Quantum computing promises to enhance machine learning and artificial intelligence. However, recent theoretical works show that, similar to traditional classifiers based on deep classical neural networks, quantum classifiers would suffer from adversarial perturbations as well. Here we report an experimental demonstration of quantum adversarial learning with programmable superconducting qubits. We train quantum classifiers, which are built on variational quantum circuits consisting of ten transmon qubits featuring average lifetimes of 150 µs, and average fidelities of simultaneous single- and two-qubit gates above 99.94% and 99.4%, respectively, with both real-life images (for example, medical magnetic resonance imaging scans) and quantum data. We demonstrate that these well-trained classifiers (with testing accuracy up to 99%) can be practically deceived by small adversarial perturbations, whereas an adversarial training process would substantially enhance their robustness to such perturbations.

Retracted: LncRNA SNHG16 Promotes Proliferation, Migration, and Invasion of Glioma Cells Through Regulating the miR-490/PCBP2 Axis.

Cancer Biotherapy and Radiopharmaceuticals officially retracts the paper entitled, "LncRNA SNHG16 Promotes Proliferation, Migration, and Invasion of Glioma Cells Through Regulating the miR-490/PCBP2 Axis," by Fangen Kong, Yang Yan, Jinfeng Deng, Yaoli Zhu, Yingqin Li, Huiqing Li, and Yiping Wang (Cancer Biother Radiopharm. E-pub ahead of print 23 Jul 2020; doi: 10.1089/cbr.2019.3535) at the authors' request: "We apologized that we have found a serious problem in our paper. In fact, the Western blot experiment in our study was commissioned a third-party company for testing. In present, some peers have found that the company has forged experimental reports. After contacting the company, they were unable to provide the original images. We have checked and confirmed that the authenticity of the data provided by the company is problematic. In view of the problems in this paper, all the authors have discussed and agreed to withdraw the paper." [sic] The journal publisher requested the name of the "third-party company," to which the authors replied: "We apologize for our mistakes. Our so-called "the third party company", after further investigation, is actually not a company but an individual person. Due to the personal reasons, the previous experimental data were lost and the original raw data could not be provided. So we can not guarantee the authenticity of those data provided by that person. Some members are considering to repeat the experiment again, but we have no way to raise enough fund to repeat it. Hence after serious discussion, we decided to withdraw the manuscript. Again we apologize sincerely for your inconvenience." [sic] Submissions from a third party are a violation of the journal's standard protocols and is considered an infraction against the rigorous standards of scientific publishing. The Editor and Publisher of Cancer Biotherapy and Radiopharmaceuticals are committed to preserving the scientific literature and the community it serves and does not tolerate any violations of scientific misconduct. Therefore, the publisher officially retracts the article.

Generation and Application of Mouse Monoclonal Antibody Against Human Cytomegalovirus UL23.

Human cytomegalovirus (HCMV) is a paradigm for pathogen-mediated immune evasion. The immune response to HCMV has been intensively studied for many years and still remains the focus of attention for numerous research groups. UL23 is an early gene of HCMV, belonging to the US22 gene family, encoding protein UL23. However, no monoclonal antibodies against to HCMV UL23 protein have been reported to prepare for the research. In this study, we prepared a highly specific monoclonal antibody against UL23 protein by alternately immunizing BALB/C mice with both UL23 recombinant protein and HCMV Towne. Recombinant protein UL23 was used as a detection antigen to screen 305 strains of hybridoma cells. One of them was identified to secrete IgG1 mAb named as 26C5. Western blotting results showed that not only the overexpressed UL23 protein in 293T cells but also the viral UL23 protein in HCMV-infected human foreskin fibroblast cells specifically were recognized by 26C5 mAb. Notably, we found that UL23 protein were enriched by 26C5 mAb in coimmunoprecipitation experiment with high potency and the native form of UL23 protein localizing primarily in the cytoplasm were recognized by 26C5 mAb in immunofluorescence assay with high specificity. The monoclonal antibody obtained in this study lays the foundation for further study of HCMV UL23 protein.

[Association between angiotensin-converting enzyme gene polymorphism and Alzheimer's disease].

OBJECTIVE: To determine the association between the polymorphism of angiotensin converting enzyme (ACE) gene and Alzheimer's disease (AD). METHODS: This case-control study involved 201 AD patients and 257 healthy subjects matched for age and gender as the control group. Polymerase chain reaction amplification and matrix-assisted laser desorption/ ionization time of flight mass spectrometry were used to examine the rs4291, rs4309, and rs4343 of ACE gene, and the difference in genotypes, allelotype frequencies and haplotype frequencies were analyzed between the two groups. RESULTS: No statistic difference was found in the genotype and allelotype frequencies of rs4291 locus between AD and control groups (P>0.05). A significant difference was found in the genotype and allelotype frequencies of rs4309 between the two groups with a significant increase in the C allelotype frequency in AD group (OR=1.917, 95% CI=1.431-2.568, P<0.05). The difference in the genotype frequency of rs4343 was not significant between the two groups, but the allelotype frequencies differed significantly with a decreased A allelotype frequency in AD group(OR=0.714, 95% CI=0.532-0.957, P=0.024). Analysis of the linkage disequilibrium among the loci of rs4291, rs4309 and rs4343 showed a D' all above 0.65 between one another. Haplotype analysis confirmed the existence of 5 haplotypes, namely ATA, ACA, TCA, TCG and TTG, indicating a negative correlation between haplotype ATA and AD occurrence (OR=0.558, 95% CI=0.420-0.741, P<0.05) and positive correlations of haplotype ACA and TCA with AD occurrence (ACA: OR=4.883, 95% CI=2.267-10.518, P<0.05; TCA: OR=2.269, 95% CI=1.083-4.754, P<0.05). CONCLUSION: The polymorphism of rs4291 may have no relation with the incidence of AD. Polymorphisms of s4309 and rs4343 may be related to AD, and ATA, ACA and TCA haplotypes composed of rs4291/rs4309/rs4343 may be related to AD.

Effect of the +781C/T polymorphism in the interleukin-8 gene on atherosclerotic cerebral infarction, and its interaction with smoking and drinking.

OBJECTIVE: The aims of this study were to investigate the association between the +781C/T polymorphism of interleukin-8 (IL-8) and atherosclerotic cerebral infarction and the interaction between the +781C/T polymorphism and smoking or drinking in cerebral infarction in the Han Chinese population. METHODS: We investigated the +781C/T polymorphism of IL-8 in 308 consecutive Han Chinese patients who were diagnosed with atherosclerotic cerebral infarction and in 294 age- and gender-matched healthy control subjects. The patients were classified using the Oxfordshire Community Stroke Project (OCSP) classification. The patients and subjects' histories of smoking and drinking were recorded, and atherosclerosis (AS) of the internal carotid artery (ICA) was evaluated in the patients. The +781C/T polymorphism was determined by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: The +781C/T polymorphism and allele frequencies were not significantly different between the patients and controls and were not significantly associated with the OCSP classifications. We found that the 781C allele was significantly associated with AS of the ICA in the patients (p = 0.017), and the CT genotype was more prevalent in patients without AS of the ICA (p = 0.035). No interactions were observed between the +781C/T polymorphism and smoking or drinking. CONCLUSION: Our results demonstrated that the +781C/T polymorphism of IL-8 did not play a role and had no interaction with smoking or drinking in the occurrence of cerebral infarction in the Han Chinese population. However, the C allele and the CT genotype might be associated with AS of the ICA in patients with ischemic stroke.

[Effect of willed movement therapy on the expression of neurotrophin 3 and growth-associated protein 43 in rats with cerebral ischemia reperfusion].

OBJECTIVE: To observe the effect of willed movement therapy on the expression of neurotrophin 3 (NT-3) and growth associated protein 43 (GAP-43) in rats with cerebral ischemia-reperfusion (IR) and investigate the neuroprotective mechanism of willed movement therapy in nerve regeneration and repair. METHODS: Cerebral IR model was established by middle cerebral artery occlusion (MCAO) in SD rats. The rats were randomly divided into MCAO group, environment modification group (EM group) and willed movement therapy group (WM group). The rats were evaluated for neurological deficits and decapitated on days 3, 7 and 15 after the reperfusion to examine the expressions of NT-3 and GAP-43 in the ischemic brain tissues by immunohistochemistry. RESULTS: Compared with MCAO and EM groups, the rats in WM group showed significantly lowered grade of neurological deficits (P<0.05) at 15 days and significantly increased the expressions of NT-3 and GAP-43 (P<0.05) at 7 and 15 days after the reperfusion. No significant difference was found in the expression of NT-3 and GAP-43 between MCAO and EM groups (P>0.05). The expression of NT-3 was positively correlated to that of GAP-43 in the ischemic tissues. CONCLUSIONS: Willed movement therapy increases the expression of NT-3 and GAP-43 in the ischemic brain area in rats with cerebral ischemia-reperfusion, which is probably related to nerve regeneration and repair.

Nanoporous titanium borophosphates with rigid gainesite-type framework structure.

Nanoporous titanium borophosphates have been synthesized which exhibit a rigid gainesite-type framework of polyhedra. The open-framework character is supported by the reversibility of de- and rehydration processes.

[Effect of willed movement therapy on GFAP and SYP expression in rats with cerebral ischemia-reperfusion].

OBJECTIVE: To determine the effect of willed movement on the expression of glial fibrillary acidic protein (GFAP) and synaptophysin (SYP) in adult rats with cerebral ischemia-reperfusion, and explore the mechanism of willed movement in promoting nerve repair and regeneration. METHODS: Adult rat models of cerebral ischemia-reperfusion injury were established by middle cerebral artery occlusion (MCAO) for 2 h followed by a 24-h reperfusion. The models were then divided randomly into 3 groups, namely the model group, environmental modification (EM) group, and willed movement (WM) group. In each group, neurological deficits were evaluated at 3, 7 and 15 days after reperfusion. Immunohistochemistry and immunofluorescence assay were employed to examine the expression of GFAP and SYP in the brain tissue near the ischemic foci. RESULTS: The rats in WM group showed lessened neurological deficits at 15 days and lowered expression of GFAP and SYP at 7 and 15 days after reperfusion compared with the model and EM groups (P<0.05). No significant difference was found in the expression of GFAP or SYP between the model group and EM group at any time points. CONCLUSION: Willed movement can promote the functional recovery of neurological deficits following cerebral ischemia-reperfusion probably in relation to enhanced GFAP and SYP expressions in the ischemic brain tissues.