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LOT wireless sensor nodes are limited by physical factors, usually have weak computing power and endurance, and wireless communication methods are very vulnerable to information theft. Therefore, it is of great significance to ensure the safe and efficient transmission of images in new application scenarios. In view of the need for an efficient image transmission, this paper combines compressed sensing technology with p-tensor product theory, applies the above theory to distributed wireless sensor networks, and uses the correlation of adjacent sensor nodes in wireless sensor networks to propose an improved a joint sparse model for measurement matrices and reduction algorithms. The feasibility is verified by simulation experiments, and the comparison between joint reconstruction and single reconstruction, and the application of various algorithms in other algorithms is carried out, and the actual completion time and storage capacity are analysed. The minimum completion time for wavelet transform is 1.29, the sparse estimated time for the selection of preliminary P waves is 0.07 and the compressed sensing time is 0.20. The maximum completion time for wavelet transform was 1.32, for sparse estimation, it is 0.62, for preliminary P-wave selection, it is 0.17, and for compressed sensing, it is 0.88. The processing time is no >3 s and the runtime is only 0.22–0.88 s. The results show that compared with the compressed sensing of a single node, the joint sparse model based on distributed compressed sensing has a smaller reconstruction error, and can achieve high-precision signal reconstruction when the measurement value is small.

Biomineralization is a phenomenon that involves the deposition of inorganic ions onto organic substrates, resulting in the formation of hard tissue materials. Tumor mineralization, on the other hand, encompasses two key aspects: tumor calcification and tumor iron mineralization. The occurrence of spontaneous tumor calcification and regional lymph node calcification in colorectal cancer, lung cancer, and glioblastoma has been established as a favorable prognostic factor in clinical settings. Building upon this understanding, we propose the concept and advance the development of a compound that artificially induces bionic mineralization around the surface of cancer cells. This process has demonstrated exceptional efficacy in inhibiting the growth and metastasis of cervical, breast, and lung tumors. Moreover, it has exhibited outstanding performance in the early-stage diagnosis of cancer. Consequently, we anticipate that this concept holds significant potential for cancer-targeted mineralization therapy and diagnosis, offering a novel avenue for the development of anticancer drugs.

Objective To investigate the efficacy and safety of superficial temporal artery (STA)⁃middle cerebral artery (MCA) bypass combined with temporoparietal fascia flap in the treatment of moyamoya disease (MMD). Methods Retrospective analysis was performed on 18 patients with MMD who were treated with STA⁃MCA bypass combined with temporoparietal fascia flap in Tianjin Huanhu Hospital from January 2018 to January 2020. The improvement of clinical symptoms, incision healing and complications were observed 7 days or 6 months after operation. DSA and PWI were used to evaluate the changes of cerebral hemodynamics, patency of bridge anastomosis and collateral compensation in pre⁃and post⁃operation. Results During the postoperative and follow⁃up period, 13 cases showed significant improvement in clinical symptoms, 4 cases showed no obvious improvement, one case was worse than before operation, 5 cases had cerebral hyperperfusion syndrome (CHS), one case had ischemic stroke, 2 cases had residual limb movement disadvantage, one case had unsteady walking, and one case had memory loss. All the patients had good wound healing during the postoperative and follow⁃up period. All operative incisions healed well, cerebral blood flow (CBF) and cerebral blood volume (CBV) were improved, mean treasnit time (MTT) and time to peak (TTP) were slightly delayed, and blood flow at the bridge anastomis was unobvious. Conclusions STA⁃MCA bypass combined temporoparietal fascia flap can effectively improve cerebral hemodynamics, increase blood flow in MCA blood supply area and intracranial cerebral perfusion, reduce the incidence of ischemic stroke, maintain the normal anatomical position and the function of the temporalis muscle, and improve postoperative comfort of patients.

Community structure is an important property of complex networks.It is profoundly significant for understanding the organizational structure and functions of complex networks.A community detection algorithm (Dynamic Distance Stochastic Competitive Learning,DDSCL) is proposed to solve the community detection problem of complex networks.DDSCL is based on dynamic distance and stochastic competitive learning.The algorithm first combines node degree values and Euclidean distances between nodes to determine the initial positions of particles in stochastic competitive learning,which will allow different particles to not compete within the same community at the beginning of the wander,speeding up the convergence of the particles.The dyna-mic distance between nodes is then combined with a dynamic distance algorithm to incorporate the dynamic distance between nodes into the particle prioritization walking process.The particle prioritization process is more directional and less random in this way.The particle travel process will also optimize the change in dynamic distance.When the particles reach a convergence state,the node is occupied by the particle that has the most control over it.Each particle in the network eventually corresponds to a community,and the community structure of the network is revealed according to the nodes occupied by each particle.DDSCL is compared in experimental tests on eight real network datasets,and it uses NMI and modularity Q -value as evaluation metrics.It’s found that DDSCL outperforms other algorithms overall.The algorithm first reduces the randomness of preferential walking of particles in stochastic competitive learning.Then DDSCL solves the problem of fragmented communities arising from dynamic distance algorithms,and improves the accuracy of community detection results.The experimental results show the proposed algorithm’s effectiveness.

In order to discuss the application and mode of the forced modulation function in a sensor, the optical fibre emphasis function was established by referring to the geometric method, the tilt factor and the shape factor of the reflecting surface. These were introduced for the first time, and the corresponding mathematical model was established. The method of numerical simulation is systematically studied and multimode optical fibre parameters (including optical fibre of axial spacing, optical fibre core diameter and numerical aperture) are adopted. The reflective surface inclination and shape factors on the RIM–FOS intensity modulation characteristics are studied according to the obtained light quasi-Gaussian distribution model, establishing a general three-intensity modulation function of fibre optic sensor. The results show that the intensity modulation characteristic of specular reflection is obviously better than that of the diffuse reflection surface, and the peak value of the modulation function is five times that of diffuse reflection. The intensity modulation characteristic decreases with increase in the roughness of the reflection surface. The system can not only complete the RIM–FOS characteristic simulation and characteristic testing functions, but can also start-up the test and not be affected by the ambient light interference and power fluctuation of the light source. The test stability is good with high repeatability.

Objective To explore the efficacy and safety of cerebral revascularization treatment for the posterior circulation ischemic stroke with chronic vertebro ⁃ basilar artery steno ⁃ occlusion. Methods From January 2018 to January 2021, 11 patients with posterior circulation ischemic stroke by chronic vertebro⁃basilar artery steno⁃occlusion were diagnosed and treated in Tianjin Huanhu Hospital. We utilized MRI to locate the infarct, CTA to assess the steno⁃occlusive site and the stenosis rate, and DSA to evaluate the collateral compensation. These patients were treated by using occipital artery (OA)⁃vertebral artery (VA) bypass, external carotid artery (ECA) ⁃ VA bypass with radial artery (RA) graft, OA ⁃ posterior inferior cerebellar artery (PICA)/anterior inferior cerebellar artery (AICA) bypass and superficial temporal artery (STA)⁃posterior cerebral artery (PCA)/superior cerebellar artery (SCA) bypass. The prognosis was assessed through modified Rankin Scale (mRS). Results The steno⁃occlusive sites confirmed by CTA were located at basilar artery(BA, 2/11), bilateral vertebr ⁃ basilar artery as tander lesions (1/11), intracranial and extracranial segments of bilateral VA (2/11 and 11/11), unilateral intracranial segment of VA with contralateral extracranial segment of VA (4/11), initial segment of unilateral VA with tenderness of contralatieral VA (1/11). Collateral patterns confirmed by DSA included posterior communicating artery (PCoA, 7/11), cerebellar pial collateral (5/11; among PICA, AICA and SCA), ascending cervical artery (AA, 4/11), cerebral pial collateral [middle cerebral artery (MCA)⁃PCA, 3/11] and anterior spinal artery (ASA, 1/11). All the 11 patients underwent bypass operation successfully. Imaging [indoleocyanine green angiography (ICGA), DSA and CTA] suggested bypass vascular patency. Two patients suffered lung infection postoperatively, one patient was suspected with intracranial infection, and all the patients got better after antibiotic treatment. The median mRS score was 1. The mean follow⁃up time was 8 months. Nine patients had good prognosis at discharge (mRS score 0-1), 2 cases had a medial prognosis (mRS score 2-3). Conclusions Cerebral revascularization treatment of chronic symptomatic severe vertebro ⁃ basilar artery steno⁃occlusive with posterior circulation ischemic stroke is effective, safe, and feasible.

Objective To investigate the efficacy and safety of low flow bypass in the treatment of chronic symptomatic middle cerebral artery occlusion (MCAO). Methods A total of 28 patients with chronic symptomatic MCAO who were treated in Tianjin Huanhu Hospital from January 2016 to December 2019 underwent superficial temporal artery⁃middle cerebral artery (STA⁃MCA) bypass, and the prognosis of neurological function was assessed by modified Rankin Scale (mRS). DSA or CTA were reexamined to evaluate the patency of the anastomotic site of the bridging vessels, and PWI was reexamined to evaluate improvement of cerebral perfusion. Results All 28 patients underwent STA⁃MCA bypass successfully, the success rate of operation was 100%, and the patency rate of bridge vessels was 100%. The postoperative neurological function was improved compared with that before operation, and the difference was statistically significant (mRS score 1.43 ± 0.57 vs. 2.14 ± 0.36; t = 6.301, P = 0.000). Twelve months after operation, the cerebral blood flow (CBF) and cerebral blood volume (CBV) of the affected side were significantly increased, and the mean transit time (MTT) and time to peak (TTP) were significantly decreased compared with those before operation. The mean postoperative follow⁃up was (39.41 ± 9.39) months. No new ischemic events occurred, and the bridge vessels were patchy. Conclusions Low flow bypass is safe and effective in the treatment of chronic symptomatic MCAO.

Numerical simulation can establish corresponding models for temperature field, molten pool shape, residential stress, microstructure evolution in the metal SLM process effectively. Meanwhile this model can accurately predict the performance of forming parts, and provide scientific basis for process parameters optimization, consequently boost the metal SLM to industry application. In this paper, the latest research progress of numerical simulation in the process of metal laser additive manufacturing was summarized, including temperature field, molten pool dynamics, residual stress and deformation in the forming part, and microstructure change.The latest progress of numerical simulation in metal SLM process was summarized, and the metal SLM process was analyzed. Finally, the future development trend was put forward that metal SLM process numerical simulation should be combined with big data, artificial intelligence, deep learning and other technologies and numerical simulation accuracy will be further improved,the processing window of metal laser additive manufacturing will be broadened,and guidance will be provided for the development of individual products.

The cross joints, which are ubiquitous in real rock mass, have significant influences on the fracture characteristics of rock mass but it has not been thoroughly studied. In this paper, the 3D printed samples with cross joints are made. The mechanical fracture characteristics of rock samples with cross joints under uniaxial compression are studied by means of acoustic emission, CT scanning technology and DIC image analysis. The results show that the relationships between fracture fractal dimension (DB) and uniaxial strength, elastic modulus and Poisson’s ratio have similar trends when the dip angle of primary joint is small, which has a better accordance than that of a much larger primary joint dip angle. There is a much better regularity of fracture mode of the former than that of the latter. When the dip angle of the primary joint is large, the clustered microfracture AE events occur under the tension between the joint and the block in the compaction and elastic stages, while this phenomenon will not occur when the dip angle of the primary joint is small. In DIC strain nephogram, the micro strain on the fracture propagation path is prior to the macro fracture. The fracture mode can be predicted by calculating the maximum area of micro strain under compression. The primary joint plays the main role in the fracture initiation angle and fracture propagation mode, and the acoustic emission and fractal characteristics are unified. When the secondary joint is parallel to the maximum principal stress, the total rock damage is mainly caused by the propagation of the primary joint, and the accumulative AE events (AAEE) and DB are the largest, implying that the fracture mode is more complex when the AAEE and DB is much larger. The three-dimensional fracture mode is mainly characterized as 2-3 tension wing fracture surfaces caused by the expansion of joints ends. On the internal three-dimensional macro fracture surface, there are discontinuous structures affected by incomplete tension failure.

Objective. This study is aimed at exploring the association between autophagy and tumor immune infiltration (TII) in colorectal cancer (CRC). Methods and Materials. We downloaded the transcriptome profiling and clinical data for CRC from The Cancer Genome Atlas (TCGA) database and obtained the normal colon transcriptome profiling data from Genotype-Tissue Expression Project (GTEx) database. The list of autophagy-related signatures was obtained from the Human Autophagy Database. We isolated the autophagy-related genes from the CRC gene expression matrix and constructed an autophagy-related prognostic (ARP) risk model. Then, we constructed a multiROC curve to validate the prognostic ability of the ARP risk model. CIBERSORT was used to determine the fractions of 22 immune cells in each CRC sample, and the association between these TII cells and CRC clinical variables was further investigated. Finally, we estimated the association of 3 hub-ARP signatures and 20 different types of TII cell distribution. Results. We classified 447 CRC patients into 224 low-risk and 223 high-risk patients using the median ARP risk score. According to the univariate survival test results, except for gender (P=0.672), age (P=0.008), cancer stage, and pathological stage T, M, and N were closely correlated with the prognosis of CRC patients (P

A solving method for the inverse-kinematics （IK） problem of a kind of 6 degree of freedom （DOF） manipulator with the axes of the 3 adjacent rotational joints in the arm part，shoulder，elbow and wrist parallel is presented. The merit of this method is that，by utilizing the geometrical relation between the end-effector，hand and wrist of the manipulator determined by its structure，the position of the wrist corresponding to a desired end-effector orientation and position can be solved at the first step in the whole calculation process. And then，the solution of a 6-variable equations，which describes the relationship between the 6 joint positions of the manipulator and its end-effector orientation and position is reduced into two 3-variable equations，one of which describes the relationship between the wrist position and the positions of 3 joints distributed in the shoulder and elbow，and the other describes the relationship between the end-effector orientation and the positions of the rest 3 joint distributed in the wrist. This method reduces the complexity of solving the IK problem of a 6 DOF manipulator. The experiment results with an UR3 manipulator shows that，the method is able to compute the joints positions，in comparison with by applying the algorithm of the UR3 controller，the end-effector positioning accuracy of the manipulator by applying the presented method is up to millimeter-scale in linear and 1 degree in angular.

High cutting temperatures are easily generated during the machining of carbon fibre reinforced plastics (CFRP) and can induce serious damage during machining such as delamination. The purpose of this paper is to study the influence of cutting temperature on the performance of CFRP after machining. CFRP specimens were heated to temperatures within the vicinity of cutting temperatures generated during machining, then air-cooled and their bending properties investigated. The results showed that temperature had significant influence on the bending stress of CFRP. With increasing temperature, bending stress decreased and was lowest when the temperature was close to the glass-transition temperature. It was concluded that the bending properties of CFRP could be seriously affected if the material temperature was close to the glass-transition temperature and maintained for a period. As a result, cutting temperature should be kept lower than the glass transition temperature during machining.

The paper takes Wuhan Iron and Steel Co., Ltd. (hereinafter referred to as “ WISCO “) energy consumption and carbon emissions as the research object, and analyzes WISCO’s carbon emissions. Through the construction of WISCO’s Long range Energy Alternatives Planning system (hereinafter referred to as LEAP) prediction model for energy consumption and carbon emissions, three scenarios have been set up: a baseline scenario, an energy efficiency improvement scenario, and an energy structure change scenario to measure WISCO’s carbon emissions. Based on the results of the LEAP model, this article puts forward the following recommendations for WISCO’s low-carbon transformation. WISCO must strictly control steel output.WISCO should introduce electric furnaces to increase the proportion of electric furnace steel. While ensuring the supply of scrap steel resources, WISCO ought to use scrap steel efficiently. In addition, introduction of hydrogen direct reduction iron technology is also crucial to WISCO in a planned way.

Variable stiffness design (VSD) has been paid more attention for its capability of further exploiting the potential of fiber-reinforced composite in composite structure design. VSD under different mechanical property indexes is reviewed in this paper. The review mostly focuses on strength, buckling, frequency, and other more common mechanical indices. Subsequently, the usage of VSD method for several years is briefly summarized. Some successful tests about variable stiffness composite parts are introduced and the experiment results are also addressed. The article summarizes the research situation from both perspectives based on a number of papers about the VSD of composite materials in recent years and provides theoretical reference and basic knowledge to new researchers.

At present, a lot of passenger cars and light trucks are equipped with the dual mass flywheel, which can decrease the non-uniformity of the indicated engine torque. In engine bench test, the secondary mass of the dual mass flywheel can’t be fixed because there is no transmission system on the test bench. As a result, the secondary mass of the dual mass flywheel will have radial and circumferential movements, which may lead to a damage to the dual mass flywheel. This paper presents an improved design of the crafting tool for the dual mass flywheel to protect the secondary mass during the engine bench test. For the improved design, the cylinder body is used for the positioning of the crafting tool, and a spline shaft and a ball bearing of centripetal adjustment are chosen to fix the secondary mass. Through this tool, the dual mass flywheel engine can be tested on the test bench without a starting shaft, and the disassembling of the engine flywheel bolts during the hot test can be avoided.