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A fundamental goal of quantum technologies concerns the exploitation of quantum coherent dynamics for the realization of novel quantum applications such as quantum computing, quantum simulation, and quantum metrology. A key challenge on the way towards these goals remains the protection of quantum coherent dynamics from environmental noise. Here, we propose a concept of a hybrid dressed state from a pair of continuously driven systems. It allows sufficiently strong driving fields to suppress the effect of environmental noise while at the same time being insusceptible to both the amplitude and phase noise in the continuous driving fields. This combination of robust features significantly enhances coherence times under realistic conditions and at the same time provides new flexibility in Hamiltonian engineering that otherwise is not achievable. We demonstrate theoretically applications of our scheme for a noise-resistant analog quantum simulation in the well-studied physical systems of nitrogen-vacancy centers in diamond and of trapped ions. The scheme may also be exploited for quantum computation and quantum metrology. [ABSTRACT FROM AUTHOR]

Background: Statin therapy has shown to deplete atherosclerotic plaque lipid content and induce plaque regression. However, how early the plaque lipid depletion can occur with low-density lipoprotein cholesterol (LDL-C) lowering in humans in vivo has not been fully described. Methods: We enrolled 43 lipid treatment naïve subjects with asymptomatic carotid atherosclerosis and LDL-C ≥ 100 and ≤ 250 mg/dl. Rosuvastatin 5–20 mg/day was used to lower LDL-C levels to < 80 mg/dl. Lipid profile and carotid MRI scans were obtained at baseline, 3, 12, and 24 months. Carotid plaque lipid-rich necrotic core (LRNC) and plaque burden were measured and compared between baseline and during treatment. Results: Among the 32 subjects who completed the study, at 3 months, an average dose of rosuvastatin of 11 mg/day lowered LDL-C levels by 47% (125.2 ± 24.4 mg/dl vs. 66.7 ± 17.3 mg/dl, p < 0.001). There were no statistically significant changes in total wall volume, percent wall volume or lumen volume. However, LRNC volume was significantly decreased by 7.9 mm3, a reduction of 7.3% (111.5 ± 104.2 mm3 vs. 103.6 ± 95.8 mm3, p = 0.044). Similarly, % LRNC was also significantly decreased from 18.9 ± 11.9% to 17.9 ± 11.5% (p = 0.02) at 3 months. Both LRNC volume and % LRNC continued to decrease moderately at 12 and 24 months, although this trend was not significant. Conclusions: Among a small number of lipid treatment naïve subjects, rosuvastatin therapy may induce a rapid and lasting decrease in carotid plaque lipid content as assessed by MRI. Trial registration: ClinicalTrials.Gov numbers NCT00885872 [ABSTRACT FROM AUTHOR]

Very recently (Cai et al 2010 Phys. Rev. E 82 021921), a simple mechanism was presented by which a molecule subjected to forced oscillations, out of thermal equilibrium, can maintain quantum entanglement between two of its quantum degrees of freedom. Crucially, entanglement can be maintained even in the presence of very intense noise, so intense that no entanglement is possible when the forced oscillations cease. This mechanism may allow for the presence of nontrivial quantum entanglement in biological systems. Here we significantly enlarge the study of this model. In particular, we show that the persistent generation of dynamic entanglement is not restricted to the bosonic heat bath model, but can also be observed in other decoherence models, e.g. the spin gas model, and in non-Markovian scenarios. We also show how conformational changes can be used by an elementary machine to generate entanglement even in unfavorable conditions. In biological systems, similar mechanisms could be exploited by more complex molecular machines or motors. [ABSTRACT FROM AUTHOR]

Bone marrow is a major site of radiation injury. The extreme sensitivity of bone marrow cells to genotoxic stress largely determines the adverse side effects of radiation. CpG-oligodeoxynucleotide (ODN) is known to be radioprotective in extramedullary hemopoiesis, but its effect on bone marrow hemopoiesis remains unknown. In this study, we investigated whether CpG-ODN ameliorated hemopoiesis radiation injury when administered after total-body irradiation (TBI). Mice were treated with 50 μg of CpG-ODN via intraperitoneal injection (i.p) 30 min., 24 and 48 hr after TBI. Our results show that CpG-ODN was able to mediate the activation of nuclear factor κB (NF-κB) via degradation of inhibitor NF-κB (IκB-α), and some oxidative stress parameters (malondialdehyde, glutathione and superoxide dismutase) showed significant differences between the radiation control group and the radiation and administration of CpG-ODN group. White blood cell count, bone marrow cell count and bone marrow histological examination indicated that CpG-ODN minimized bone marrow damage induced by radiation. Exogenous colony-forming unit-spleen count indicated that CpG-ODN reduced primitive hemopoietic stem cell damage and reconstituted the hemopoietic system after TBI. The survival of mice was also enhanced after various levels of TBI. The calculated dose reduction factor was 1.2. Thus, we conclude that CpG-ODN may contribute to the amelioration of hemopoiesis radiation injury. [ABSTRACT FROM AUTHOR]

In this study, we have aimed to evaluate the relationship between the shape and location of superficial calcification and the presence of fibrous cap rupture and intraplaque hemorrhage in atherosclerotic carotid plaque. Sixty-three patients with carotid stenosis underwent contrast-enhanced high resolution MR examinations with a 3-T MR scanner and 226 slices with superficial calcification were evaluated in the study. The shape of superficial calcification was categorized as the irregular type (dotted/arcuated) and patchy type and the location of superficial calcification was categorized as the marginal type and central type. Intraplaque hemorrhage and fibrous cap rupture depicted on the same slice as superficial calcification were identified. The chi-squared test was used for statistical analysis. A total of 149 slices (65.9%) with intraplaque hemorrhage and 107 slices(47.3%)with fibrous cap rupture were detected. There were 191 slices with irregular type (dotted/arcuated) calcification and 166 slices with marginal type calcification. Irregular superficial calcification was found more frequently accompanied with intraplaque hemorrhage as compared to the patchy type (73.8 vs. 22.9%, P < 0.0001); there was a significant difference between the marginal type and the central type for the accompaniment of intraplaque hemorrhage (72.9 vs. 46.7%, P < 0.05). However, there was no significant difference between different shapes and locations of superficial calcification that accompanied with fibrous cap rupture ( P > 0.05). This study showed that superficial calcification is an important factor for determination of instability of atherosclerotic carotid plaque. The shape and location of superficial calcification are important features associated with the occurrence of intraplaque hemorrhage. [ABSTRACT FROM AUTHOR]

Abstract  There is growing evidence in recent years that the pristine fullerene may be endowed with strong pro-oxidant capacity to biological samples. In this investigation we tested the hypothesis that water-soluble fullerene-C60 (nano-C60) may interact with ionizing radiation enhancing its antiproliferative effects. The two tumor cell lines with different radiosensitivity B16 and SMMU-7721 were treated by a combination of pristine fullerene and 60Co ? irradiation. We measured cell survival rates, apoptotic characteristics, reactive oxygen species (ROS) production and alteration of cell diameter with or without ?-irradiation. There was reduced survival with B16 and SMMU-7721 cells exposed to nano-C60, with the inhibitory concentrations reducing the viability by 50% to 65 part per billion (ppb) and 150 ppb respectively. For cells exposed to nano-C60 prior to ?-irradiation, damage to cell membranes and increased numbers of apoptotic cells were detected by morphologic Hoechst-staining analysis and Annexin V/propidium iodide double-staining. In cells exposed to nano-C60, there were increased levels of ROS, as measured by fluorescence detection under laser confocal microscopy. Preincubation with non-toxic pristine C60 before ?-ray caused enlargement of cells with increased diameter. The results show that nano-C60 inhibits the growth of tumor cells at certain concentrations and increases the effects of 60Co ?-irradiation, possibly through the elevated production of cellular ROS and the membrane disruption. Data in this study indicates a possible consideration of using C60 as a candidate of sensitization modifier in tumor radiation biology. [ABSTRACT FROM AUTHOR]

Purpose. To provide sample size calculation for the quantitative assessment of carotid atherosclerotic plaque using non-invasive magnetic resonance imaging in multi-center clinical trials. Methods. As part of a broader double-blind randomized trial of an experimental pharmaceutical agent, 20 asymptomatic placebo-control subjects were recruited from 5 clinical sites for a multi-center study. Subjects had 4 scans in 13 weeks on GE 1.5 T scanners, using TOF, T1-⁄PD-⁄T2- and contrast-enhanced T1-weighted images. Measurement variability was assessed by comparing quantitative data from the index carotid artery over the four time points. The wall⁄outer wall (W⁄OW) ratio was calculated as wall volume divided by outer wall volume. The percent lipid-rich⁄necrotic core (%LR⁄NC) and calcification (%Ca) were measured as a proportion of the vessel wall. For %LR⁄NC and %Ca, only those subjects that exhibited LR⁄NC or Ca components were used in the analysis. Results. Measurement error was 5.8% for wall volume, 3.2% for W⁄OW ratio, 11.1% for %LR⁄NC volume and 18.6% for %Ca volume. Power analysis based on these values shows that a study with 14 participants in each group could detect a 5% change in W⁄OW ratio, 10% change in wall volume, and 20% change in %LR⁄NC volume (power = 80%, p < .05). The calculated measurement errors presume any true biological changes were negligible over the 3 months that subjects received placebo. Conclusion. In vivo MRI is capable of quantifying plaque volume and plaque composition, such as %lipid-rich/necrotic core and %calcification, in the clinical setting of a multi-center trial with low inter-scan variability. This study provides the basis for sample size calculation of future MRI trials. [ABSTRACT FROM AUTHOR]

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Radiation‐induced lung injury (RILI) is a serious complication in thoracic tumour radiotherapy. It often occurs in clinical chest radiotherapy and acute whole‐body irradiation (WBI) caused by nuclear accidents or nuclear weapon attack. Some radioprotective agents have been reported to exert protective effects when given prior to radiation exposure, however, there is no treatment strategy available for preventing RILI. In this study, we demonstrated that heat‐killed Salmonella typhimurium (HKST), a co‐agonist of Toll‐like receptors 2 (TLR2), Toll‐like receptors 4 (TLR4) and Toll‐like receptors 5 (TLR5), mitigated radiation‐induced lung injury through the transforming growth factor‐β (TGF‐β) signalling pathway. We found that HKST alleviated lung hyperaemia and pathological damage after irradiation, indicated that HKST inhibits the early inflammatory reaction of radiation‐induced lung injury. Then, for the first time, we observed HKST reduced collagen deposit induced by irradiation in the later phase (7‐14 week) of RILI, and we found that HKST inhibited radiation‐induced cell apoptosis in lung tissues. We found that HKST reduced the level of TGF‐β and regulated its downstream signalling pathway. Finally, it was found that HKST inhibited radiation‐induced epithelial–mesenchymal transition (EMT) in lung tissues. In conclusion, our data showed that HKST effectively mitigated RILI through regulating TGF‐β, provide novel treatment strategy for RILI in whole‐body irradiation and radiotherapy. [ABSTRACT FROM AUTHOR]

Endotoxin damage is an acute, multi-organ disease, the most typical symptoms of which are liver injury and inflammatory cytokine storm. Endotoxin tolerance is described as the pretreatment of lipopolysaccharides (LPS) before the toxin invasion, which is consistent with the adaptive response induced by low-dose radiation (LDR). In this study, we verified that LDR could resist the endotoxin damage by suppressing the increase of inflammatory cytokines, including interleukin 6, tumor necrosis factor, and NO, to improve the survival and relieve the inflammatory cell infiltration, in which low dose of LPS performed consistently with LDR. [ABSTRACT FROM AUTHOR]

Background/Aims: Ovarian cancer (OC) is the fifth leading cause of cancer-related death in women, and it is difficult to diagnose at an early stage. The purpose of this study was to explore the prognostic biological markers of OC. Methods: Univariate Cox regression analysis was used to identify genes related to OC prognosis from the Cancer Genome Atlas(TCGA) database. Immunohistochemistry was used to analyse the level of SPINK13 in OC and normal tissues. Cell proliferation, apoptosis and invasion were performed using MTT assay, flow cytometric analysis and Transwell assay, respectively. Results: We identified the Kazal-type serine protease inhibitor-13 (SPINK13) gene related to OC prognosis from the Cancer Genome Atlas (TCGA) database by univariate Cox regression analysis. Overexpression of SPINK13 was associated with higher overall survival rate in OC patients. Immunohistochemistry showed that the level of SPINK13 protein was significantly lower in OC tissues than in normal tissues (P < 0.05).In vitro experiments showed that the overexpression of SPINK13 inhibited cellular proliferation and promoted apoptosis. Moreover, SPINK13 inhibited cell migration and epithelial to mesenchymal transition (EMT). SPINK13 was found to inhibit the expression of urokinase-type plasminogen activator (uPA), while recombinant uPA protein could reverse the inhibitory effect of SPINK13 on OC metastasis. Conclusion: These results indicate that SPINK13 functions as a tumour suppressor. The role of SPINK13 in cellular proliferation, apoptosis and migration is uPA dependent, and SPINK13 may be used as a potential biomarker for diagnosis and targeted therapy in OC. [ABSTRACT FROM AUTHOR]

The radical pair reaction underlies the magnetic field sensitivity of chemical reactions and is suggested to play an important role in both chemistry and biology. Current experimental evidence is based on ensemble measurements; however, the ability to probe the radical pair reaction at the single-molecule level would provide valuable information concerning its role in important biological processes. Here, we propose a scheme to detect the charge recombination rate in a radical pair reaction under ambient conditions by using single nitrogen-vacancy center spin in diamond. We demonstrate theoretically that it is possible to detect the effect of the geomagnetic field on the radical pair reaction and propose the present scheme as a possible hybrid model chemical compass. [ABSTRACT FROM AUTHOR]

Quantum criticality, as a fascinating quantum phenomenon, may provide significant advantages for quantum sensing. Here we propose a dynamic framework for quantum sensing with a family of Hamiltonians that undergo quantum phase transitions (QPTs). By giving the formalism of the quantum Fisher information (QFI) for quantum sensing based on critical quantum dynamics, we demonstrate its divergent feature when approaching the critical point. We illustrate the basic principle and the details of experimental implementation using quantum Rabi model. The framework is applicable to a variety of examples and does not rely on the stringent requirement for particular state preparation or adiabatic evolution. It is expected to provide a route towards the implementation of criticality-enhanced quantum sensing. [ABSTRACT FROM AUTHOR]

Quantum sensing exploits the fundamental features of a quantum system to achieve highly efficient measurement of physical quantities. Here, we propose a strategy to realize a single-qubit pseudo-Hermitian sensor from a dilated two-qubit Hermitian system. The pseudo-Hermitian sensor exhibits divergent susceptibility in a dynamical evolution that does not necessarily involve an exceptional point. We demonstrate its potential advantages to overcome noises that cannot be averaged out by repetitive measurements. The proposal is feasible with the state-of-art experimental capability in a variety of qubit systems, and represents a step towards the application of non-Hermitian physics in quantum sensing. [ABSTRACT FROM AUTHOR]

Single-qubit measurements are typically insufficient for inferring arbitrary quantum states of a multiqubit system. We show that, if the system can be fully controlled by driving a single qubit, then utilizing a local random pulse is almost always sufficient for complete quantum-state tomography. Experimental demonstrations of this principle are presented using a nitrogen-vacancy (NV) center in diamond coupled to a nuclear spin, which is not directly accessible. We report the reconstruction of a highly entangled state between the electron and nuclear spin with fidelity above 95% by randomly driving and measuring the NV-center electron spin only. Beyond quantum-state tomography, we outline how this principle can be leveraged to characterize and control quantum processes in cases where the system model is not known. [ABSTRACT FROM AUTHOR]

We propose a novel strategy to reconstruct the quantum state of dark systems, i.e., degrees of freedom that are not directly accessible for measurement or control. Our scheme relies on the quantum control of a two-level probe that exerts a state-dependent potential on the dark system. Using a sequence of control pulses applied to the probe makes it possible to tailor the information one can obtain and, for example, allows us to reconstruct the density operator of a dark spin as well as the Wigner characteristic function of a harmonic oscillator. Because of the symmetry of the applied pulse sequence, this scheme is robust against slow noise on the probe. The proof-of-principle experiments are readily feasible in solid-state spins and trapped ions. [ABSTRACT FROM AUTHOR]

We experimentally observe Floquet Raman transitions in the weakly driven solid-state spin system of a nitrogen-vacancy center in diamond. The periodically driven spin system simulates a two-band Wannier-Stark ladder model and allows us to observe coherent spin state transfer arising from a Raman transition mediated by Floquet synthetic levels. It also leads to the prediction of an analog photon-assisted Floquet Raman transition and dynamical localization in a driven two-level quantum system. The demonstrated rich Floquet dynamics offers new capabilities to achieve effective Floquet coherent control of a quantum system with potential applications in various types of quantum technologies based on driven quantum dynamics. In particular, the Floquet Raman system may be used as a quantum simulator for the physics of periodically driven systems. [ABSTRACT FROM AUTHOR]

The implementation of quantum entangling gates between qubits is essential to achieve scalable quantum computation. Here, we propose a robust scheme to realize an entangling gate for distant solid-state spins via a mechanical oscillator in its thermal equilibrium state. By appropriate Hamiltonian engineering and usage of a protected subspace, we show that the proposed scheme is able to significantly reduce the thermal effect of the mechanical oscillator on the spins. In particular, we demonstrate that a high entangling gate fidelity can be achieved even for a relatively high thermal occupation. Our scheme can thus relax the requirement for ground-state cooling of the mechanical oscillator, and may find applications in scalable quantum information processing in hybrid solid-state architectures. [ABSTRACT FROM AUTHOR]

Background and Purpose: This study aimed to investigate the arterial disease risk factors for the progression of intraplaque hemorrhage (IPH) in patients with carotid atherosclerosis using serial high-resolution magnetic resonance (MR) imaging., Methods: Consecutive symptomatic patients who had MRI evidence of intraplaque hemorrhage present in the ipsilateral carotid artery with respect to the side of the brain affected by stroke or TIA were recruited in the study. All the patients underwent follow-up MR imaging at least 6 months after baseline. The annual change in IPH and other carotid plaque morphology was calculated, and a tertile method was used to classify the plaques as progressed or not with respect to IPH volume using the software CASCADE. Logistic regression and receiver operating characteristic (ROC) curve were conducted to evaluate the risk factors for the progression of IPH., Results: A total of thirty-four symptomatic patients (mean age: 67.1 years, standard deviation [SD]: 9.8 years, 27 men) were eligible for the final analysis, and contralateral plaques containing IPH were seen in 11 of these patients (making 45 plaques with IPH in total). During mean 16.6-month (SD: 11.0 months) follow-up, the overall annual change in IPH volume in 45 plaques with IPH was mean -10.9 mm 3 (SD: 49.1 mm 3 ). Carotid plaques were significantly more likely to be classified in progressed IPH group if the patient was taking antiplatelet agent at baseline (OR: 9.76; 95%CI: 1.05 to 90.56; p = 0.045), had a baseline history of current or past smoking (OR: 9.28; 95%CI: 1.26 to 68.31; p = 0.029), or had a larger baseline carotid plaque-containing vessel wall volume (OR: 1.36 per 10 mm 3 ; 95%CI: 1.02 to 1.81; p = 0.032) after adjustments for confounding factors. ROC analysis indicated that the combination of these three risk factors in the final model produced good discriminatory value for the progressed IPH group (area under the curve: 0.887)., Conclusions: Taking an antiplatelet agent at baseline, a baseline history of current or past smoking and larger baseline carotid plaque-containing vessel wall volume were independently predictive of plaques being in the progressed IPH group. Our findings indicate that awareness and management of such risk factors may reduce the risk of intraplaque hemorrhage progression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mingming, Peng, Lichen, Shaohua, Fei, Hongtao, Shitong, Yao, Xihai and Jianming.)