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Parkinson’s disease (PD) is a neurodegenerative disorder that predominantly affects dopaminergic neurons in the substantia nigra and ventral tegmental area, resulting in symptoms such as tremors, muscle rigidity, bradykinesia, and potential cognitive and affective disturbances. The effective delivery of pharmacological agents to the central nervous system is hindered by various factors, including the restrictive properties of the blood‒brain barrier and blood‒spinal cord barrier, as well as the physicochemical characteristics of the drugs. Traditional drug delivery methods may not provide the therapeutic concentrations necessary for functional restoration in PD patients. However, lipid-based nanoparticles (NPs) offer new possibilities for enhancing the bioavailability of established treatment regimens and developing innovative therapies that can modify the course of the disease. This review provides a concise overview of recent advances in lipid-based NP strategies aimed at mitigating specific pathological mechanisms relevant to PD progression. This study also explores the potential applications of nanotechnological innovations in the development of advanced treatment modalities for individuals with PD.

Objective: This paper puts forward one cylinder driving five-row longan core-removing mechanism for the low production efficiency of the pneumatic longan core-removing mechanism. Methods: The mechanism adopts one cylinder driving five rows handspikes in the direction, which transport longan to core-removing hole, after the longan is cut under the triangular blade, and another cylinder drives five handspikes in the vertical direction in order to remove longan core. Five longan cores is removed one working process, so that the production efficiency is improved. Results: The result of experiments showed that the order of influencing on longan core-removing loss rate is blade thickness, flow rate, mandril diameter, pneumatic pressure and the interaction of flow rate and pneumatic pressure. Conclusion: When blade thickness is fixed at 2.5 mm, mandril diameter at 6.0 mm, pneumatic pressure at 0.6 MPa, flow rate at 6 m3/h, the core-removing loss rate achieves the lowest value, which is 7.04%.

BACKGROUND There are large amounts of copper-lead-zinc polymetallic sulfide ore resources in Yunnan Province, China, but the efficient separation of these resources remains a major problem. OBJECTIVES To improve the separation efficiency of valuable minerals in mixed concentrates. METHODS In this study, the major elemental content, phase composition, mineral composition, particle size characteristics, and monomer liberation degree of a mixed concentrate were analyzed using a variety of modern detection methods such as chemical analysis, X-ray diffraction, and mineral liberation analysis (MLA). RESULTS The results showed that the mixed concentrate had fine particles, and some minerals occurred as intergrowths or inclusions. The monomer liberation degree of the target minerals chalcopyrite, galena, and sphalerite was medium to low, ranging from 69.28% to 70.56%. It was preliminarily predicted that the theoretical separation efficiencies of copper, lead, and zinc in the mixed concentrate were 71.63%, 62.97% and 72.72%, respectively. CONCLUSIONS Improving the grinding fineness of mixed concentrates to promote the full liberation of metal minerals is a key way to improve the separation efficiency of copper, lead, and zinc minerals.

Background: Atrial appendage tachycardia (AAT) originating from the atrial appendage (AA) is extremely difficult to eliminate using radiofrequency catheter ablation (RFCA). The optimal management strategy for AAT refractory to RFCA remains unclear.Objective: This study aims to investigate the long-term result of ablative therapy and the optimal alternative management for AAT refractory to RFCA.Methods: A total of 51 patients with AAT originating from the AA undergoing RFCA were recruited. Video-assisted atrial appendectomy and oral ivabradine were performed on those with AATs refractory to RFCA, and this study aimed to evaluate their safety and long-term efficacy.Results: We included 51 patients (51/586, 8.7%) with AATs confirmed by activation mapping and contrast venography. Among them, there were 28 (54.9%) AATs originating from the distal AA. In total, 14 (27.4%) AATs were refractory to RFCA, including 13 originating from the distal AA and one arising from the proximal AA. Ten of 11 (90.9%) AATs originating from the distal AA were eliminated after an atrial appendectomy, and the other three AATs were suppressed using oral ivabradine. Origins from the distal AA refractory to RFCA and early age of AAT onset ≤26.5 years indicated the need for atrial appendectomy. No major complications occurred, and nine patients with tachycardia-induced cardiomyopathy fully recovered. Long-term success was achieved in 98.0% of patients with multiple treatment managements.Conclusion: AATs originating from the distal AA were more refractory to RFCA. RFCA was the cornerstone of AAT catheter ablation. Video-assisted thoracoscopic atrial appendectomy was an effective strategy for those origins at the distal AA and the age of AAT onset ≤26.5 years. Ivabradine represents a promising treatment for AAT temporarily in pediatric and young adult patients.

BACKGROUND In the Western Yunnan, there is an abundance of low-grade gold resources with uneven grain size, complicated ore structure and incomplete separation. Using the traditional mineralogical analysis process, it is difficult to achieve accurate and rapid determination of the occurrence of gold and the inlay characteristics of gold-bearing minerals. OBJECTIVES To study the mineralogy process of polymetallic gold ores in Western Yunnan. METHODS:The mineral composition, dissemination size, and inclusions characteristics of gold ores were analyzed, and the effect of mineralogical properties of gold-bearing minerals on the recovery of gold was determined. The X-ray Fluorescence Spectrometer and eight-lamp flame graphite furnace integrated Atomic Absorption Spectrometer were used for the analysis of ore properties, and the ore samples were analyzed by Mineral Liberation Analysis. RESULTS The results show that gold is mainly in the form of free gold, with superfine dissemination size of gold minerals, mainly concentrated on the 0.01 mm to 0.02 mm granularity level. Gold smaller than 0.074 mm presents as free monomer natural gold, which accounts for 50.08% of the total gold. Other gold occurs as inclusions in pyrite, magnetite and chalcopyrite. However, the gold-bearing minerals have small grain size, poor dissociation, and uneven embedding. CONCLUSIONS Increasing the dissociation degree of major gold-bearing minerals is an important method for increasing gold recovery.

Averaging of multiple scans is often used in magnetic resonance imaging (MRI) to increase the signal-to-noise ratio (SNR). However, image averaging often results in movement-induced blurs of the edges and tissue details. A matched and weighted averaging (MWA) method has been proposed by our group to obtain images with reduced blurring effects in signal averaging. Here a rotation-invariant non-local means (RINLM) algorithm was proposed, which used circular patches consisted of series of rings with equal area, instead of square patches, to search for similar patches in the images. Compared with the non-local means (NLM) algorithm, the RINLM algorithm was capable of finding more similar patches in the images containing many rotated local structure. This method was used to process noisy images to improve the SNR, and validated using both phantom images and in vivo MR images. The results demonstrated that the method could improve the SNR, while better preserving the edges and details of the images.

Reconstruction, post-processing and visualization of images are important parts of magnetic resonance imaging (MRI). In this work, a new open source framework, namely Yet Another Pipeline (YAP), was proposed for reconstruction, post-processing and visualization of MR images. With YAP, researchers can build customized image-processing pipelines with ease. Compared with the existing open source frameworks, YAP has the following features: (1) it has an interface-based design, enabling function extension by plugin development; (2) it uses a script language with straightforward grammar, making it easy to build and modify customized pipelines; (3) it supports branches in the pipelines, facilitating pipeline building and debugging. YAP has been implemented on a commercial MRI system.

Both compressed sensing (CS) and parallel imaging (PI) can be used to accelerate magnetic resonance imaging (MRI) by under-sampling the k space data. Several methods combining CS and PI have been proposed to further improve the scanning speed. In this paper, we proposed a new approach to combine CS and PI. We used GRAPPA (Generalized Autocalibrating Partially Parallel Acquisitions) algorithm to reconstruct local under-sampled k space data, and CS to reconstruct the whole k space data for each coil. In the CS reconstruction step, we constrained that the reconstructed k space data should be assimilated to both the sampled k space data and the reconstructed k space data by GRAPPA. In addition, we designed a new sampling strategy to improve the quality of image reconstruction. In vivo imaging results demonstrated that the proposed approach could effectively remove artifacts and improve the image quality.

The hydro-mechanical transmission（ HMT） is obtained by connecting hydraulic transmission and mechanical transmission in parallel. It has the advantages of high torque of hydraulic transmission and high mechanical transmission efficiency. The dual hydro-mechanical transmission（ DHMT） is connected by two sets of double flow. The components of the DHMT system are modeled and the shifting control strategy of DHMT system is proposed based on the established dynamics model. The co-simulation model of DHMT is built based on AMEsim and Simulink. Finally,the simulation results are analyzed and the correctness of the shifting control strategy is verified.

C26H24Cl2N6O14, monoclinic, P21/c (no. 14), a = 15.7471(18) Å, b = 14.1486(15) Å, c = 13.7894(15) Å, β = 109.588(3)°, V = 2894.5(6) Å3, Z = 4, Rgt(F) = 0.0744, wRref(F2) = 0.2246, T = 293(2) K.

C13H11N3O3, Orthorhombic, Pna21 (no. 33), a = 9.2062(6) Å, b = 11.5258(7) Å, c = 11.5263(7) Å, V = 1223.04(13) Å3, Z = 4, Rgt(F) = 0.0377, wRref(F2) = 0.1006, T = 293(2) K.

There are large amounts of refractory copper-zinc polymetallic sulfide ore resources in the Simao region of Yunnan Province. Traditional mineral identification under microscope is difficult to automatically accurately determine copper, zinc and other valuable metals due to their complex mineral structure and composition. Methods of chemical, polarized light microscopic analysis and Mineral Liberation Analysis (MLA) were conducted to study the elements composition, mineral species, disseminated and inclusions characteristics of the sulfide ores. The results show that the ore contains about 3.03% Cu, 0.13% Pb, 3.90% Zn and 27.44% S. The main metallic minerals include chalcopyrite, pyrite, sphalerite and minor galena. The objective minerals of chalcopyrite and sphalerite are intergrowth and wrapped with pyrite. More than 96% of chalcopyrite, sphalerite and pyrite are distributed on a larger size than 9.6 μm, which are in the range of easy mineral processing. Galena is finely disseminated and its grinding dissociation with other sulfide minerals is difficult. Based on the process mineralogy research results, the ore needs to be ground to approximately 31 μm to achieve the dissociation of Cu-Zn-S sulfide minerals, and to approximately 14 μm to achieve the dissociation of Pb-Cu-Zn-S sulfide minerals. The theory recovery of Cu is 91.22% and Zn is 84.92%. These results are very important to develop mineral processing technology and select indicators for refractory sulfide ore.

Statistical learning method of support vector machine and its application in risk management of coal marketing were introduced according to characteristics of coal marketing management. The experiments showed that the method can evaluate credit risk of customers and help coal enterprises to select quality customers, which offers decision basis to coal enterprises for actively preventing and avoiding marketing risks.

The paper proposed a scheme of framework of intelligent mine system based on Internet of things on the basis of analyzing construction status of intelligent mine. It introduced structure of Internet of things of mine and construction of application system of intelligent mine in details. The scheme has a reference function for constructing Internet of things system of coal enterprises.