Quantum phase transitions (QPTs) are usually associated with many-body systems in the thermodynamic limit when their ground states show abrupt changes at zero temperature with variation of a ...parameter in the Hamiltonian. Recently it has been realized that a QPT can also occur in a system composed of only a two-level atom and a single-mode bosonic field, described by the quantum Rabi model (QRM). Here we report an experimental demonstration of a QPT in the QRM using a
Yb
ion in a Paul trap. We measure the spin-up state population and the average phonon number of the ion as two order parameters and observe clear evidence of the phase transition via adiabatic tuning of the coupling between the ion and its spatial motion. An experimental probe of the phase transition in a fundamental quantum optics model without imposing the thermodynamic limit opens up a window for controlled study of QPTs and quantum critical phenomena.
Objectives
Sarcopenia, an age-related decrease in muscle mass and function, is associated with several potential adverse health outcomes. Its association with another age-related syndrome, dysphagia ...remains unclear. This systematic review and meta-analysis aims to explore the association between sarcopenia and dysphagia.
Methods
PubMed, Embase, Scopus and CINAHL were searched for cross-sectional, case-control and cohort studies that investigated the association between sarcopenia and dysphagia. First author, publication year, study type, sample size, inclusion and exclusion criteria, participant demographics, definition and measurement for evaluation of sarcopenia and dysphagia, main outcomes were retrieved. The association between sarcopenia and dysphagia were expressed by odds ratio (OR) and 95% confidence interval (CI).
Results
9 studies are eligible in the systematic review, and 5 cross-sectional studies comprising 913 participants which showed dichotomous classification of sarcopenia and dysphagia were included in the meta-analysis. The crude odds ratios (ORs) were extracted from 5 studies, and 4 of them also provide adjusted ORs. The crude ORs between sarcopenia and dysphagia is 6.17 (95% CI, 3.81-10.00), after adjusting for some confounders, such as age, sex, Barthel Index score, nutritional status, sarcopenia is also have an association with dysphagia (adjusted ORs, 4.06; 95% CI, 2.27-7.29). The subgroup analysis showed that there was no significant difference between different sarcopenia diagnostic criteria, assessment tools of skeletal muscle mass and dysphagia.
Conclusion
Sarcopenia was positively associated with dysphagia. Prevention and screening of dysphagia is essential among sarcopenic old patients. The causal relationship requires more prospective cohort study for confirmation.
This study takes stock of business and economics research on Artificial Intelligence (AI) and provides a dynamic panorama of the overall knowledge structure of this ever-growing body of work ever ...since its inception in 1966. Our bibliometric analysis based on the full archive of 1024 studies identifies the main trends of and the major intellectual contributors to the extant knowledge of AI in business and economics research. Specifically, our results show that (1) AI-focused business and economics research wintnessed growth over three stages, particularly with a sharp increase after 2017. (2) While this body of research has gained tremendous momentum across the globe, the United States is by far the center of knowledge generation. (3) Research collaborations are still limited in this area. (4) Research topics flourished, ranging from early decision support systems, neural networks, and scheduling methods to more recent machine learning, automation, and big data. This study also identifies fruitful avenues for further business and economics research with an AI focus.
The anomalous rod shape in carbon isotopes has been investigated in the framework of the cranking covariant density functional theory, and two mechanisms to stabilize such a novel shape with respect ...to the bending motion, extreme spin, and isospin are simultaneously discussed for the first time in a self-consistent and microscopic way. By adding valence neutrons and rotating the system, we have found the mechanism stabilizing the rod shape; i.e., the σ orbitals (parallel to the symmetry axis) of the valence neutrons, important for the rod shape, are lowered by the rotation due to the Coriolis term. The spin and isospin effects enhance the stability of the rod-shaped configuration. This provides a strong hint that a rod shape could be realized in nuclei towards extreme spin and isospin.
Non-Hermitian systems generically have complex energies, which may host topological structures, such as links or knots. While there has been great progress in experimentally engineering non-Hermitian ...models in quantum simulators, it remains a significant challenge to experimentally probe complex energies in these systems, thereby making it difficult to directly diagnose complex-energy topology. Here, we experimentally realize a two-band non-Hermitian model with a single trapped ion whose complex eigenenergies exhibit the unlink, unknot, or Hopf link topological structures. Based on non-Hermitian absorption spectroscopy, we couple one system level to an auxiliary level through a laser beam and then experimentally measure the population of the ion on the auxiliary level after a long period of time. Complex eigenenergies are then extracted, illustrating the unlink, unknot, or Hopf link topological structure. Our work demonstrates that complex energies can be experimentally measured in quantum simulators via non-Hermitian absorption spectroscopy, thereby opening the door for exploring various complex-energy properties in non-Hermitian quantum systems, such as trapped ions, cold atoms, superconducting circuits, or solid-state spin systems.
The Y-stent technique, including crossing-Y and kissing-Y, is a promising therapeutic option for some complex bifurcation aneurysms. Here, its efficacy and safety are evaluated on the basis of 11 ...bifurcation aneurysms.
A retrospective review was conducted for all patients who underwent endovascular treatment of aneurysms in our department between January 2009 and June 2011 to identify and analyze cases with bifurcation aneurysms reconstructed by using Y-stents.
Eleven patients (4 ruptured and 7 unruptured aneurysms) were identified (4 men, 7 women) with a mean age of 60.4 years. Nine aneurysms (2 AcomAs, 3 MCA-Bifs, 1 PcomA, 3 BA apexes) were treated by using the crossing-Y technique, and 2 (both BA apexes) were treated with the kissing-Y technique, achieving complete occlusion in 6 aneurysms, residual neck in 4, and partial occlusion in 1. Perioperatively, a single thromboembolic event occurred in 1 case without neurologic deficit, which required a salvaging second stent implantation. Means of 9.9 months of angiographic and 13.7 months of clinical follow-up were available. As a result, 9 (81.8) aneurysms were completely occluded, 1 with a residual neck remained stable, and 1 residual aneurysm sac was recanalized, which was retreated and achieved a complete occlusion. All patients were independent with an mRS score of 0-1 at discharge and follow-up.
In selected patients, the reconstruction of bifurcation aneurysms by using the Y-stent can be successfully achieved with satisfactory midterm results.
A genome-wide association study (GWAS) in the Japanese population identified 2 new Parkinson disease (PD) susceptibility loci on 1q32 (PARK16) (OMIM 613164) and BST1. We analyzed single nucleotide ...polymorphism (SNPs) located at the GWAS-linked loci (PARK16, PARK8, PARK1, and BST1) in a Chinese population and also conducted a meta-analysis in Asians by pooling 2 independent replication studies from Japan.
We conducted an analysis of 13 SNPs associated with PD GWAS-linked loci in 2 case-control cohorts comprised of 1,349 ethnic Chinese subjects.
PARK16, PARK8, and PARK1 loci but not BST1 were found to be associated with PD. PARK16 SNPs were associated with a decreased risk while PARK1 and PARK8 SNPs were associated with an increased risk of PD. A pooled analysis of our Chinese cohorts and 2 Japanese replication cohorts involving 1,366 subjects with PD and 16,669 controls revealed robust association with these 3 loci and also BST1. There was a trend toward a stronger protective effect of SNPs at the PARK16 locus in sporadic PD compared to familial cases and in older compared to younger subjects.
Our study reaffirms the role of GWAS-linked loci in PD in Asian subjects and the strength of association is similar between Chinese and Japanese subjects. Efforts to elucidate the associated gene within PARK16 locus are warranted.
T-cell malignancies, mainly known as T-cell acute lymphoblastic leukemia (T-ALL) and T-cell non-Hodgkin's lymphoma (T-NHL), are aggressive tumors. Although the clinical outcome of the patients has ...improved dramatically with combination chemotherapy, significant challenges remain, including understanding of the factors that contribute to the malignant behavior of these tumor cells and developing subsequently optimal targeted therapy. Aberrant cell signal transduction is generally involved in tumor progression and drug resistance. This review describes the pathogenetic role of multiple cellular signaling pathways in T-cell malignancies and the potential therapeutic strategies based on the modulation of these key signaling networks.
Abstract Background The preoperative predictors of microvascular invasion (MVI) in multinodular hepatocellular carcinoma (HCC) are currently unclear. Methods We retrospectively analyzed 266 patients ...who underwent potentially curative resection of multinodular HCC. MVI was diagnosed on pathological examination in 64 patients. Preoperative risk factors for MVI were identified and survival curves were analyzed. Results Patients with MVI had significantly lower overall and recurrence-free survival rates than those without MVI (overall survival, 1 year: 86% vs. 71%, 3 years: 58% vs. 16%; recurrence-free survival, 1 year: 69% vs. 12%; 3 years: 48% vs. 12%; both P < 0.001). Multivariate analysis showed that serum alpha-fetoprotein (AFP) level >400 μg/L (odds ratio OR = 3.732, P = 0.016), serum gamma-glutamyltransferase (GGT) level >130 U/L (OR = 19.779, P < 0.001), total tumor diameter >8 cm (OR = 5.545, P = 0.010), and tumor number >3 (OR = 11.566, P = 0.007) were independent predictors of MVI. A scoring system was constructed, and the MVI rate was significantly higher in patients with a score of ≥3 than those with a score of <3 (64.1% vs. 10.9%, P < 0.001). Overall and recurrence-free survival rates were significantly lower in patients with a score of ≥3 (both P < 0.001). Conclusions Serum AFP level >400 μg/L, serum GGT level >130 U/L, total tumor diameter >8 cm, and tumor number >3 were preoperative predictors of MVI in patients with multinodular HCC. In patients with a high risk of MVI and well-preserved liver function, anatomic resection may be worth considering.
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