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W−Re alloys were prepared by powder metallurgy. The effect of annealing temperature on the microstructure and properties of the W−Re alloys were investigated by tensile mechanical properties testing, hardness testing, and optical microscope analysis. The results show that, the room temperature tensile strength of the forged W−Re alloys is 1620 MPa, the elongation after fracture is 20%, and the Vickers hardness is HV30 540. Local recrystallization occurs at 1500 ℃ and the grain growth occurs at 1700 ℃. The room temperature tensile strength and hardness of the W−Re alloys decrease with the increase of annealing temperature, and the elongation after fracture first increases and then decreases with the increase of annealing temperature.

The article borrows game theory to analyze the development dilemma of new rural cooperative economic organizations. A rural cooperative economic organization that is based on game theory is proposed by describing the new rural cooperative economic organization and game theory. According to the subject of interest, the basic assumptions of the model are determined, and the game theory model for rural cooperative economic organizations is constructed by combining the basic assumptions and relevant variables, and the evolutionary stabilization strategy solution process is given at the same time. The development status of new rural cooperative economic organizations in the context of information technology is evaluated using the model mentioned above. When E2 = 0.18, the probability of both parties choosing {cooperation, cooperative} strategy will increase to 82.3%. And E2 = 0.82 will reduce the probability of forming complete cooperation to 71.5% through the introduction of cost and benefit distribution, supervision and punishment mechanisms to achieve a win-win situation for the community of interest, but there is still the probability of the two sides cooperating to choose the optimal strategy will become smaller, revealing that the current development of the rural cooperative economic organization has problems and shortcomings. In order to improve the development of cooperative economic organizations in rural areas, relevant strategies are proposed.

The decrease of vestibular function is mainly due to the organic changes of vestibular and surrounding tissues, resulting in the disorder of balance function elements. It is commonly seen in cochlear vestibular diseases and nerve center lesions. However, vestibular function impairment caused by radiotherapy is rarely reported. This paper reports a case of vestibular function impairment after radiotherapy in a patient with brain metastasis of lung cancer, who developed dizziness 2 months after the completion of whole brain radiotherapy. The patient had walking instability, vestibular ataxia, limb weakness, and progressive aggravation, accompanied by tinnitus, hearing loss. With ameliorating microcirculation and vestibular rehabilitation training, the patient’s dizziness symptoms were improved while the postular instability continued to exist. High dose of radiation can make vestibular hair cells atrophy, vestibular capillary brittle idiopathic changes, resulting in the loss of semircular canalcysts and ampullae of nerve sensory epithelium, and vestibular hair cells may lose medullary nerve fibers. More oxygen free radicals, excessive oxygen free radicals during radiotherapy may cause hair cell lipid peroxidation or vascular degeneration, microcirculatory element disorder, damaging the elliptic cyst and balloon plaque supporting cells and hair loss of cells, vascular damage, and vestibular dysfunction.

The effects of sputtering technological parameters (sputtering power, pressure, and time) on properties of stainless steel (SS)-sputtered polyester (PET) fiber were investigated. The variations in properties such as surface morphology, tensile strength, abrasion resistance, and electromagnetic shielding effectiveness of the prepared PET fiber sputtered under various parameters were discussed. The results indicated that the uniformity and denseness of the sputtered SS film were positively dependent upon the predetermined sputtering variables. The properties such as the breaking strength and abrasion resistance of SS-sputtered PET were remarkably enhanced as compared to the pristine one. It was found that the disorientation of macromolecules in fiber was mainly responsible for the deteriorated strength following wet and/or dry heating. In addition, a woven fabric composed of SS-sputtered fiber exhibited electromagnetic shielding capability. This research indicates that the metal deposition onto textile surfaces using magnetron sputtering is a straightforward approach for potential use in multifunctional materials.

The Cu/Ag nanostructured film that follows Volmer–Weber growth pattern was successfully deposited onto PP fiber surface using the magnetron sputtering technique.

Objective To evaluate the effects of preconditioning with Toll-like receptor 4 (TLR4) inhibitor on hypoxic-ischemic hippocampal neurons and dendritic spines in neonatal rats. Methods Seventy-five neonatal (7-day-old) rats were randomly divided into control group, hypoxia-ischemia group (HI group) and TAK-242 (a TLR4-specific antagonist) group. In the latter 2 groups, rat models of hypoxic-ischemic brain damage (HIBD) were established using the Rice method, and in TAK-242 group, a single dose of TAK-242 (0.5 mg/kg) was intraperitoneally injected 30 min prior to HI. Western blotting was used to detect TLR4 expression in the left hippocampus of the rats 24 h after HI. On day 21 following the modeling, HE staining, Nissl staining and Golgi silver staining were used to assess neuronal loss and the changes in dendritic spine density in the left hippocampus. The expression of N-methyl-D-aspartic acid receptors 2A and 2B (NR2A and NR2B) was detected using Western blotting and immunofluorescence staining. Results The expression of TLR4 in the left hippocampus of the neonatal rats increased significantly at 24 h after HI (P < 0.05), and TAK-242 obviously suppressed the up-regulated expression of TLR4 (P < 0.05). Compared with those in the control group, the number of neurons, dendritic spine density and the expression of NR2A all decreased significantly in the left hippocampus of the rats at 21 d after HI (P < 0.05); pretreatment with TAK-242 obviously alleviated these changes (P < 0.05). Conclusion TLR4 inhibitor can mitigate HI-induced long-term damage of the hippocampal neurons and the dendritic spines.

[Purpose/significance] Collaborative innovation is the strategic choice and fundamental driving force to orderly relieve Beijing's non-capital functions and promote coordinated development of Jing-Jin-Ji region. [Method/process]According to the strategic needs of collaborative development of Jing-Jin-Ji Region, this paper proposed the design ideas and general framework of collaborative innovation and development map system based on GIS. Then system application was demonstrated from three aspects, i.e. spatial distribution characteristics and stock analysis of innovation resources, the correlation analysis among innovation subjects, and the information integration display of innovation spatial pattern.[Result/conclusion] It can be concluded that the system can effectively process innovation resource space data and attribute data, and vividly show spatial distribution of innovation resources and collaborative development trend in Jing-Jin-Ji region. It is efficient to track and monitor regional development trend of collaborative innovation in time and is helpful to reveal innovation resources spatial distribution characteristics and existing problems, providing data for the collaborative innovation development level and efficiency evaluation in Jing-Jin-Ji region.

Background: Guidance has showed positive effects on promoting inquiry-based learning in science education. While an increasing number of studies focus on the design of guidance in simulation-based inquiry learning due to recent technology developments, how different designs of a same type of guidance affect learning remains a question. Objectives: This study reviews the (quasi-)experimental research on the learning effects of differently designed guidance in simulation-based inquiry learning in the past decade (2011-2020). The investigation is guided by two questions: how differently designed guidance affects inquiry-based learning in simulated environments in terms of learning process and learning outcomes, and what role technology plays in the design of guidance. In particular, we report on studies that compares the effects of a same type (process constraints/prompts/heuristics/scaffolds/metacognitive supports/direct presentation of information) of guidance with different instructional designs, and select a total of 28 peer-reviewed journal articles. The results indicate no equivocal tendency of effectiveness towards a specific design. Instead, each type of guidance has related factors that may influence its effectiveness. Three major factors that related to optimization of inquiry learning guidance in simulation-based environments are identified: the learner factor, the pedagogical factor, and the technological factor.