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Abstract The vacancy effect in quantum spin liquid (QSL) has been extensively studied. A finite density of random vacancies in the Kitaev model can lead to a pileup of low-energy density of states (DOS), which is generally experimentally determined by a scaling behavior of thermodynamic or magnetization quantities. Here, we report detailed muon spin relaxation (μSR) results of H3LiIr2O6, a Kitaev QSL candidate with vacancies. The absence of magnetic order is confirmed down to 80 mK, and the spin fluctuations are found to be persistent at low temperatures. Intriguingly, the time-field scaling law of longitudinal-field (LF)-μSR polarization is observed down to 0.1 K. This indicates a dynamical scaling, whose critical exponent of 0.46 is excellently consistent with the scaling behavior of specific heat and magnetization data. All the observations point to the finite DOS with the form $$N(E)\sim {E}^{-\nu }$$ N ( E ) ∼ E − ν , which is expected for the Kitaev QSL in the presence of vacancies. Our μSR study provides a dynamical fingerprint of the power-law low-energy DOS and introduces a crucial new insight into the vacancy effect in QSL.

Abstract Lycibarbarspermidines are unusual phenolamide glycosides characterized by a dicaffeoylspermidine core with multiple glycosyl substitutions, and serve as a major class of bioactive ingredients in the wolfberry. So far, little is known about the enzymatic basis of the glycosylation of phenolamides including dicaffeoylspermidine. Here, we identify five lycibarbarspermidine glycosyltransferases, LbUGT1-5, which are the first phenolamide-type glycosyltransferases and catalyze regioselective glycosylation of dicaffeoylspermidines to form structurally diverse lycibarbarspermidines in wolfberry. Notably, LbUGT3 acts as a distinctive enzyme that catalyzes a tandem sugar transfer to the ortho-dihydroxy group on the caffeoyl moiety to form the unusual ortho-diglucosylated product, while LbUGT1 accurately discriminates caffeoyl and dihydrocaffeoyl groups to catalyze a site-selective sugar transfer. Crystal structure analysis of the complexes of LbUGT1 and LbUGT3 with UDP, combined with molecular dynamics simulations, revealed the structural basis of the difference in glycosylation selectivity between LbUGT1 and LbUGT3. Site-directed mutagenesis illuminates a conserved tyrosine residue (Y389 in LbUGT1 and Y390 in LbUGT3) in PSPG box that plays a crucial role in regulating the regioselectivity of LbUGT1 and LbUGT3. Our study thus sheds light on the enzymatic underpinnings of the chemical diversity of lycibarbarspermidines in wolfberry, and expands the repertoire of glycosyltransferases in nature.

Background: In recent years, transcatheter aortic valve replacement (TAVR) has emerged as a pivotal treatment for pure native aortic regurgitation (PNAR). Given patients with severe aortic regurgitation (AR) are prone to suffer from pulmonary hypertension (PH), understanding TAVR’s efficacy in this context is crucial. This study aims to explore the short-term prognosis of TAVR in PNAR patients with concurrent PH. Methods: Patients with PNAR undergoing TAVR at Zhongshan Hospital, Affiliated with Fudan University, were enrolled between June 2018 to June 2023. They were categorized based on pulmonary artery systolic pressure (PASP) into groups with or without PH. The baseline characteristics, imaging records, and follow-up data were collected. Results: Among the 103 patients recruited, 48 were afflicted with PH. In comparison to PNAR patients without PH, the PH group exhibited higher rates of renal dysfunction (10.4% vs. 0.0%, p = 0.014), increased Society of Thoracic Surgeons scores (6.4 ± 1.9 vs. 4.7 ± 1.6, p < 0.001), and elevated Nterminal fragment of pro–brain natriuretic peptide (NT-proBNP). Transthoracic ultrasound examination revealed that patients with PH displayed lower left ventricular ejection fraction, larger left ventricle dimension, and more frequent moderate to severe tcuspid regurgitation (TR). Following TAVR, both groups experienced significant reductions in PASP, mitral regurgitation (MR) and TR. There were no significant differences in the incidence of postoperative adverse events in patients with or without PH. Conclusions: We found TAVR to be a safe and effective treatment for patients with PNAR and PH, reducing the degree of aortic regurgitation and PH without increasing the risk of postoperative adverse events.

Abstract Objectives To investigate the clinical efficacy and safety of bronchial thermoplasty (BT) in treating patients with chronic obstructive pulmonary disease (COPD). Methods Clinical data of 57 COPD patients were randomized into the control (n = 29, conventional inhalation therapy) or intervention group (n = 28, conventional inhalation therapy plus BT). Primary outcomes were differences in clinical symptom changes, pulmonary function-related indicators, modified Medical Research Council (mMRC), 6-min walk test (6MWT), COPD assessment test (CAT) score and acute exacerbation incidence from baseline to an average of 3 and 12 months. Safety was assessed by adverse events. Results FEV1, FEV1(%, predicted) and FVC in both groups improved to varying degrees post-treatment compared with those pre-treatment (P

Background: Quantum image processing is rapidly developing in the field of quantum computing, and it can be successfully implemented on the Noisy Intermediate-Scale Quantum (NISQ) device. Quantum image encryption holds a pivotal position in this domain. However, the encryption process often encounters security vulnerabilities and entails complex computational complexities, thereby consuming substantial quantum resources. To address this, the present study proposes a quantum image encryption algorithm based on four-dimensional chaos.Methods: The classical image is first encoded into quantum information using the Generalized Quantum Image Representation (GQIR) method. Subsequently, the trajectory of the four-dimensional chaotic system is randomized, and multi-dimensional chaotic keys are generated to initially encrypt the pixel values of the image. Then, the Arnold transformation is applied to randomly encrypt the pixel positions, resulting in the encrypted image. During the decryption process, the inverse process of encryption is employed to restore the original image.Results: We simulated this process in the Python environment, and the information entropy analysis experiment showed that the information entropy of the three encrypted images reached above 7.999, so the system has good encryption. At the same time, the correlation of the pixel distribution after the encryption algorithm is weak, which proves that the control parameters of the chaotic system can effectively reduce the correlation between pixels in the image. In the final key space analysis, the key space issued by our encryption can reach $10140\gg 2128$.Conclusion: Our method is resistant to destructive attacks and can produce scrambled images with higher encryption and usability. This algorithm solves the problems of general encryption algorithms such as periodicity, small key space, and vulnerability to statistical analysis, and proposes a reliable and effective encryption scheme. By making full use of the characteristics of Arnold transformation permutation, ergodicity and the randomness of the four-dimensional chaotic system, the encryption algorithm uses the larger key space provided by the four-dimensional Lorenz system.

Neck pain is often caused by cervical degenerative diseases, which is easy to cause adverse effects on neck function and quality of life of patients. To provide the best and effective diagnosis and treatment plan, the National University of Health Sciences published its evidence-based clinical practice guidelines for neck pain in 2019. The author in fully study the latest version guidelines on the basis of diagnosis and treatment content, from the diagnosis, treatment, matters needing attention in three aspects, and search the relevant literature research longitudinal contrast multiple high quality neck pain guidelines, from the biomechanics and neurobiological analysis of scientific treatment, and combined with the analysis of Chinese diagnosis and treatment status that the recommended treatment and treatment process is feasible in China, based on this that should through existing evidence-based medical evidence combined with Chinese Traditional Medicine guide clinical practice, hope to reference to domestic clinical treatment today.