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Objective: Femoral head necrosis is a challenging condition in orthopaedics, and the occurrence of collapse is an important factor affecting the prognosis of femoral head necrosis. Sclerosis bands are known to influence the collapse of the femoral head, yet there is a lack of research on the biomechanical role of sclerosis bands in non‐vascularized fibular grafting surgery. This study aims to evaluate the biomechanical impact of sclerosis bands in femoral head necrosis and their role in non‐vascularized fibular grafting surgery (NVFG) using finite element analysis. Methods: We constructed 11 finite element models based on CT scan data of a normal hip joint, simulating different sclerosis band thicknesses and defect scenarios. The models were analyzed for changes in femoral head displacement and von Mises stress. We constructed a hip joint model based on CT data from a normal hip joint, and after reconstruction, assembly, and optimization using 3‐matic. We created five groups consisting of 11 finite element analysis models of the hip joint. Mesh partitioning and mechanical parameter settings were performed in ANSYS. The changes and differences in femoral head displacement and von Mises stress of these models were analyzed. Results: Increasing sclerosis band thickness led to reduced peak displacement of the femoral head by 28.6%, 42.9%, and 47.6%, and increased surface von Mises stress by 28.3%, 13.8%, and 13.0%, respectively. Post‐surgery, peak displacement decreased in all groups compared to pre‐surgery levels. Increasing sclerosis band thickness post‐surgery resulted in decreased maximum von Mises stress of the femoral head by 13.9%, 3.0%, and 8.1%. Defect volume in the defect groups correlated with increased peak displacement of the femoral head by 10.0%, 30.0%, and 100.0%, and increased surface maximum von Mises stress of the femoral head by 9.3%, 14.0%, and 15.1%. Conclusion: Sclerosis band formation exacerbates von Mises stress concentration on the femoral head surface. However, thicker sclerosis bands improve post‐NVFG stability and mechanical performance. Larger anterior lateral sclerosis band defects significantly compromise postoperative stability, increasing the risk of collapse. Protecting the anterior lateral sclerosis band during NVFG surgery is crucial. [ABSTRACT FROM AUTHOR]

Irritable Bowel Syndrome (IBS) is a complex functional gastrointestinal disorder primarily characterized by chronic abdominal pain, bloating, and altered bowel habits. Chronic abdominal pain caused by visceral Hypersensitivity (VH) is the main reason why patients with IBS seek medication. Significant research effort has been devoted to the efficacy of acupuncture as a non-drug alternative therapy for visceral-hyperalgesia-induced IBS. Herein, we examined the central and peripheral analgesic mechanisms of acupuncture in IBS treatment. Acupuncture can improve inflammation and relieve pain by reducing 5-hydroxytryptamine and 5-HT3A receptor expression and increasing 5-HT4 receptor expression in peripheral intestinal sensory endings. Moreover, acupuncture can also activate the transient receptor potential vanillin 1 channel, block the activity of intestinal glial cells, and reduce the secretion of local pain-related neurotransmitters, thereby weakening peripheral sensitization. Moreover, by inhibiting the activation of N-methyl-D-aspartate receptor ion channels in the dorsal horn of the spinal cord and anterior cingulate cortex or releasing opioids, acupuncture can block excessive stimulation of abnormal pain signals in the brain and spinal cord. It can also stimulate glial cells (through the P2X7 and prokinetic protein pathways) to block VH pain perception and cognition. Furthermore, acupuncture can regulate the emotional components of IBS by targeting hypothalamic-pituitary-adrenal axis-related hormones and neurotransmitters via relevant brain nuclei, hence improving the IBS-induced VH response. These findings provide a scientific basis for acupuncture as an effective clinical adjuvant therapy for IBS pain. [ABSTRACT FROM AUTHOR]

Elemental profiles are frequently applied to identify the geographical origin and authenticity of food products, to guarantee quality. The concentrations of fifteen major, minor, and trace elements (Na, Mg, K, Ca, Al, Fe, Mn, Cu, Zn, Rb, Sr, Li, Cd, Cs, and Ba) were determined in soils, “Meili” grapes, and wines from six regions in China by inductively coupled plasma mass spectrometry (ICP-MS). The elemental concentrations in these samples, according to the geographical origins, were analyzed by one-way analysis of variance (ANOVA) with Duncan’s multiple comparisons. The bioconcentration factor (BCF) from soil to grape and the transfer factor (TF) from grape to wine were calculated. Mg, K, Ca, Cu, Zn, Rb, Sr, and Ba presented higher BCF values than the other seven elements. The TF values of six elements (Na, Mg, K, Zn, Li, and Cs) were found to be greater than one. Moreover, the correlation of element content between the pairs of soil–grape, grape–wine, and bioconcentration factor (BCF)–environmental factor were analyzed. Significant correspondences among soil, grape, and wine were observed for K and Li. Two elements (Sr and Li) showed significant correlations between BCF and environmental factor (relative humidity, temperature, and latitude). A linear discriminant analysis (LDA) with three variables (K, Sr, Li) revealed a high accuracy (>90%) to determine the geographical origin for different Chinese regions. [ABSTRACT FROM AUTHOR]

The Quantum Key Distribution protocol can encode a single quantum state and implements an information-theoretically secure key distribution protocol in communication. In the actual QKD experimental system, there are usually two encoding methods which are phase encoding and polarization encoding. Ma et al (Phase-Matching Quantum Key Distribution, Phys. Rev. X., 2018, 83) proposed the phase-matching QKD protocol, which has high transmission and it is an extension of the measurement device independent QKD. This paper successfully gives the polarization scheme of this PM-QKD protocol, the bases in the polarization scheme are arbitrary, and eliminates detector side channel attacks. Furthermore, we give the security analysis and simulation results of the polarization scheme, and compare it with the BB84 protocol. The simulation results show that our protocol is superior to the BB84 protocol in terms of transmission distance under the fixed key rate. [ABSTRACT FROM AUTHOR]

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The low-rank property of the channel covariances can be adopted to reduce the overhead of the channel training in massive MIMO systems. In this paper, with the help of the virtual channel representation, we apply such property to both time-division duplex and frequency-division duplex systems, where the time-varying channel scenarios are considered. First, we formulate the dynamic massive MIMO channel as one sparse signal model. Then, an expectation maximization-based sparse Bayesian learning framework is developed to learn the model parameters of the sparse virtual channel. Specifically, the Kalman filter (KF) and the Rauch–Tung–Striebel smoother are utilized to track the model parameters of the uplink (UL) spatial sparse channel in the expectation step. During the maximization step, a fixed-point theorem-based algorithm and a low-complex searching method are constructed to recover the temporal varying characteristics and the spatial signatures, respectively. With the angle reciprocity, we recover the downlink (DL) model parameters from the UL ones. After that, the KF with the reduced dimension is adopt to fully exploit the channel temporal correlations to enhance the DL/UL virtual channel tracking accuracy. A monitoring scheme is also designed to detect the change of model parameters and trigger the relearning process. Finally, we demonstrate the efficacy of the proposed schemes through the numerical simulations. [ABSTRACT FROM AUTHOR]

Ultra-small mesoporous silica nanoparticles (MSNs) have been synthesized at room temperature with particle sizes ranging from 28 to 45 nm. These MSNs have been employed as heterogeneous supports for palladium and gold nanocatalysts. The colloidal nature of the MSNs is highly useful for catalytic applications as it allows for better mass transfer properties and a more uniform distribution of the nanocatalysts in solution. The two nanocatalysts were evaluated in the cycloisomerization of alkynoic acids and demonstrated to produce the corresponding alkylidene lactones in good to excellent yields under mild conditions. In addition to their high activity, the catalysts exhibit low degree of metal leaching and straight-forward recycling, which highlight the practical utility of MSNs as supports for nanocatalysts. [ABSTRACT FROM AUTHOR]