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It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition (RST) in an appropriate way. This paper uses actor network theory (ANT) to construct a theoretical framework for the study of RST. Taking two typical villages with different transition paths in rural areas of North China Plain as examples, this paper reveals the mechanism of RST and makes a comparative analysis. The results show that: 1) after identifying problems and obligatory passage point, key actors recruit heterogeneous actors into the actor network by entrusting them with common interests, and realize RST under the system operation. 2) Rural settlements under different transition paths have similarities in the problems to be solved, collective actions and policy factors, but there are differences in the transition process, mechanism and effect. The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough. In contrast, the degree of RST of retention development path is limited if there is no resource and location advantage. 3) Based on the applicable conditions of different paths, this paper designs a logical framework of ‘Situation-Structure-Behavior-Result’ to scientifically guide the identification of RST paths under the background of rural revitalization.

The whole bamboo mere made directly into cellulose composites, which greatly reduced massive energy consumption from the mechanical pre-processing process.The wall thickness of transparent whole bamboo can reach 6.23 mm.The modified whole bamboo possesses excellent optical transmittance of about 60% at 6.23 mm, the illuminance of 1000 luminance (lux), water absorption stability (the mass change rate less than 4%), longitudinal tensile strength (46.40 MPa), and surface properties (80.2 HD).The combination of excellent transmittance, mechanical properties, surface properties, thermal performance, and electromagnetic shielding properties makes this composite attractive in areas such as transparent, energy-saving, and electromagnetic shielding buildings.

In exercising skeletal muscle, vasoconstrictor responses to α‐adrenoceptor activation are attenuated in part by nitric oxide (NO) produced by the neuronal isoform of NO synthase (nNOS), which is expressed constitutively in skeletal muscle cells. In skeletal muscle of pregnant animals, nNOS mRNA is upregulated, suggesting that muscle nNOS expression is modulated by the steroid hormone oestrogen. Whether oestrogen‐induced changes in nNOS expression have measurable effects on vasoregulation in skeletal muscle is unknown. In this study, we hypothesized that oestrogen deficiency would reduce muscle nNOS expression, resulting in impaired modulation of sympathetic vasoconstriction in exercising skeletal muscle. Compared to gonadally intact rats, we found that ovariectomized (OVX) rats were characterized by greater sympathetic vasoconstriction in contracting hindlimb and reduced nNOS, but not eNOS, in skeletal muscle. In addition, NOS inhibition resulted in a greater enhancement of sympathetic vasoconstriction in contracting hindlimbs of intact compared to OVX rats. These effects of oestrogen deficiency were prevented by chronic treatment of OVX rats with 17β‐oestradiol, but not with chronic progesterone or acute oestradiol. Further analysis revealed that skeletal muscle nNOS correlated directly with plasma 17β‐oestradiol and inversely with the magnitude of sympathetic vasoconstrictor responses in contracting hindlimbs. These data indicate that NO‐dependent attenuation of sympathetic vasoconstriction in contracting skeletal muscle is impaired in oestrogen‐deficient female rats, and suggest that this impairment may be mediated by reduced skeletal muscle nNOS expression.

The afferent pathways mediating respiratory load perception are still largely unknown. To assess the role of lung vagal afferents in respiratory sensation, detection of inspiratory resistive loads was compared between 10 double-lung transplant (DLT) recipients with normal lung function and 12 healthy control (Nor) subjects. Despite a similar unloaded and loaded breathing pattern, the DLT group had a significantly higher detection threshold (2.91 ± 0.5 vs. 1.55 ± 0.3 cmH2O · l−1· s) and Weber fraction (0.50 ± 0.1 vs. 0.30 ± 0.1) compared with the Nor group. These results suggest that inspiratory resistive load detection occurs in the absence of vagal afferent feedback from the lung but that lung vagal afferents contribute to inspiratory resistive load detection response in humans. Lung vagal afferents are not essential to the regulation of resting breathing and load compensation responses.

This study investigated the role of lung vagal afferents in the respiratory-related evoked potential (RREP) response to inspiratory occlusions by using double-lung transplant recipients as a lung denervation model. Evoked potential recordings in response to inspiratory occlusions were obtained from 10 double-lung transplant (DLT) recipients with normal lung function and 12 healthy control (Nor) subjects under the attend, ignore, and unoccluded conditions. Results demonstrated that early-latency RREP components (P1, P1a, Nf, and N1) were not significantly different between the DLT and the Nor groups. The late-latency RREP component (P3) was identifiable in all DLT subjects during the attend trial. However, P3latency was significantly longer in the DLT group compared with the Nor group. The zero-to-peak amplitude of P3was also significantly smaller in the DLT group than that in the Nor group during the attend trial. These results suggest that lung vagal afferents were not essential to elicit RREP responses, but may contribute to the cognitive processing of respiratory stimuli.