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[Objective] In 2013, the Ministry of Environmental Protection of China published the urban air quality ranking for the first time, and expanded the scope of the ranking in 2018, so as to assess the emission reduction effect of this system, which is of great significance for exploring new ways to improve air quality in China. [Methods] In this study, we took the urban air quality ranking system as a quasi-natural experiment and systematically analyzed the emission reduction effect of the urban air quality ranking based on the panel data of 282 Chinese cities at the prefecture level and above from 2009 to 2021 by using the staggered difference-in-differences method. [Results] (1) The urban air quality ranking system had obvious emission reduction effects. Compared with the unranked cities, the industrial sulfur dioxide emissions of the ranked cities decreased by 18.6% on average, and the emission reduction effect was more significant in the northern and inland regions. (2) Industrial structure optimization and green technology innovation were important channels through which the urban air quality ranking system influenced industrial pollution emissions. (3) Further analysis revealed that the emission reduction effect of the air quality ranking system was enhanced with the increase of Internet penetration; the system had a more obvious effect on pollution reduction in the bottom-ranked cities; and the system can significantly reduce the concentration of major air pollutants in cities and realize the expected system goals. [Conclusion] Publication of urban air quality ranking is an effective environmental information disclosure system, which provides incentives for local governments to strengthen industrial pollution control and thus improve urban air quality. Therefore, air quality rankings should be fully utilized as a “pushback” for urban air quality, and healthy competition between cities in air quality should be formed effectively.

In this paper, the importance of modern packaging design and pattern design and the application of pattern design in modern packaging design are the first two aspects of achieving the development of information integration of packaging design and pattern design, and the visual design based on Markov random field is proposed for the image retrieval and classification problems in traditional model packaging design and pattern design. Wavelet transforms, multi-scale analysis of image texture features and region merging conditions in visual design using GBIS algorithm, and image retrieval in pattern design are examined and analyzed. The results show that the model trained with both loss functions has the best retrieval top-k accuracy on both datasets, reaching 54.3% on the DARN dataset and 3.9% accuracy on Deep Fashion. This paper demonstrates the model’s effectiveness for modifying and retrieving pattern design image attributes.

The purpose of this study is to investigate the efficacy of bilateral upper-limb training (BULT) in helping people with upper-limb impairments due to stroke or brain illness regain their previous level of function. Patients recuperating from a stroke or cerebral disease were given the option of undergoing BULT or conventional training to enhance their upper-limb function. Participants were randomly allocated to one of the several different fitness programs. Results from the action research arm test, Box and block test, Wolf motor function test, Fugal–Meyer evaluation, and any other tests administered were taken into account. Some researchers have found that exercising with BULT for just 30 min per day for 6 weeks yields significant results. There were a total of 1,411 individuals from 10 randomized controlled trials included in this meta-analysis. Meta-analysis findings revealed that biofeedback treatment outperformed conventional rehabilitation therapy in reducing lower leg muscular strain, complete spasm scale score, electromyography score, and inactive ankle joint range of motion. An analysis of the literature found that BULT improved limb use in people who had suffered a stroke and hemiplegia but it did not provide any additional benefit over unilateral training.

[Objective] Northeast China, with its unique resources advantages, provides one-third of China’s commodity grain, making it a crucial part of national food security. Analyzing the spatial distribution, spatiotemporal evolution, and driving forces of grain crop cover types and cropping patterns in Northeast China is crucial for preserving the region’s “black soil granary”. [Methods] Based on Google Earth Engine (GEE), this study integrated existing crop cover type product from 2017 to 2019 with remote sensing extraction results of major grain crops from 2019 to 2021, analyzed the spatiotemporal change characteristics of grain crop planting types and cropping patterns, then revealed the driving forces by using geodetector. [Results] (1) Using phenological information, a multi-feature random forest classification method was employed to effectively extract three major grain crops: maize, soybean, and rice. In 2019, a high Kappa coefficient of 0.908 was achieved, indicating high classification accuracy and consistency in terms of area. (2) In the past five years, the shifting of grain crops from soybeans to maize has been the dominant trend in Northeast China. The shift types include soybean to maize to maize, soybean to soybean to maize, and maize to maize to soybean, accounting for 29.4%, 24.9%, and 19.1% of the total transition area, respectively. The cropping patterns of grain crops in Northeast China exhibit high spatial heterogeneity, with the maize continuous cropping pattern, rice continuous cropping pattern, and soybean-maize continuous-preference rotation pattern accounted for 46.2 %, 23.5 %, and 13.2 % of the total cropping patterns area, respectively. (3) The spatiotemporal dynamics of cropping patterns was significantly driven by natural and anthropogenic factors. Elevation, topographic wetness index, slope, rice price fluctuation, and soybean price fluctuation were important single factors that explain the spatiotemporal changes of cropping patterns. The interactive explanatory power of elevation, active accumulated temperature slope, and economic policy factors was high, and in descending order from elevation∩soybean subsidy variation, elevation∩active accumulated temperature slope, elevation∩fertilization cost variation, elevation∩rice subsidy variation, to elevation∩maize price variation. [Conclusion] During the period from 2017 to 2021, there was a notable shift in the major grain crop cover types in Northeast China, characterized by a transition from soybean to maize, while rice cultivation remained consistent. The spatial distribution of different cropping patterns was influenced by a combination of factors including topography, economy, and policy.

To produce the porous coating on the inner wall of the pipe is an effective way to enhance heat transfer performance and improve heat exchange efficiency. The electric explosion spraying method was employed to produce the porous coating on the inner wall of the pipe. The surface morphology, roughness and pore distribution of the coating under different initial voltages were studied. The mechanism for the formation of the coating was investigated by the deposition energy and explosive products explained. The results indicate that the initial voltage of the electric explosion spraying influences the microstructure of coating. The optimal porous coating can be obtained when the initial voltage of the electric explosion spraying is 14.0 kV. The optimal porous coating is formed by the accumulation of the small particles. Moreover, the optimal porous coating is obtained, the surface area is 4.47 times that of the uncoated pipe and the porosity of the ideal coating is 57.8%. The uniform round porous coating is formed, when the initial voltage of the electric explosion spraying is 15.2 kV. The porosity of those coating is 40.3%. The formation of the coating depends on the energy deposited on the copper wire during the explosion. The energy deposited on the copper wire acts as the thermodynamic condition for the sprayed particles, determines the energy and particle size of the sprayed particles and the states of the sprayed particles collide with the surface of the base tube or the particles accumulate or form a molten pool. Finally, it influences the microscopic morphology of the coating.

[Objective] The establishment of National Key Ecological Functional Areas (NKEFAs) is one of the ecological policies with wide coverage and important impact on the ecological environment in China in recent years. Exploring the impact of NKEFAs on local residents’ income is crucial for the sustainability of the policy and the balance between protection and development. [Methods] In this study, the response of local rural residents’ income to NKEFAs establishment from 2007 to 2018 was investigated at the county scale based on the propensity score matchingdifference-in-differences (PSM-DID) model, taking the establishment of the NKEFAs as a quasi-natural experiment. [Results] The results show that, in general, the establishment of the NKEFAs had significantly increased the income of local rural residents. Compared with counties not designated as the NKEFA, the per capita income of rural residents in counties designated as the NKEFA increased by 3.6%. However, significant spatial heterogeneities existed. The NKEFAs in western China had a significant positive impact on the income of rural residents, with their income increasing by 4.9%, while the NKEFAs in the eastern and central regions had no significant impact on the income of rural residents. This study further examined the differences in the impact among four different types of ecological functional zones: the establishment of soil and water conservation type and biodiversity protection type of NKEFAs had significantly increased the income of rural residents, with enhancements of 2.8% and 10.6%, respectively. But the establishment of water conservation type and windbreak and sand fixation type of NKEFAs reduced the income of local rural residents. [Conclusion] Therefore, the establishment of the NKEFAs helped achieve poverty reduction in general. The country needs to further implement policies according to local conditions and strive to achieve a “win-win” situation between ecological protection and social and economic development in the future.

Abstract Background Selecting an appropriate and personalized Gn starting dose (GSD) is an essential procedure for determining the quality and quantity of oocytes in the controlled ovarian stimulation (COS) process of the in-vitro fertilization (IVF) treatment cycle. The current approach for determining the GSD is mainly based on the experience of a clinician, lacking unified and scientific standards. This study aims to establish a prediction model of GSD, based on which good COS outcomes can be achieved with the influencing factors comprehensively evaluated quantitatively. Material and methods We collected a total of 1555 patients undergoing the first oocytes retrieving cycle and conducted correlation analysis to find the significant factors related to the GSD. Two GSD models are built based on two popular machine learning approaches, and the one with better model performance is selected as the final model. Finally, clinical application and validation were conducted to verify the effectiveness of the proposed model. Results (1) Age, duration of infertility, type of infertility, body mass index (BMI), antral follicle count (AFC), basal follicle stimulating hormone (bFSH), estradiol (E2), luteinizing hormone (LH), anti-Müllerian hormone (AMH) and COS treatment regimen were closely related to the GSD (P

The most commonly used experimental model for preclinical studies on peripheral nerve regeneration is the sciatic nerve injury model. However, no experimental study has been conducted to evaluate acute injury modes at the same time.

Clinical specialist nurses play an important role in outpatient nursing of integrated Traditional Chinese and western medicine. In order to make the outpatient nursing of integrated Traditional Chinese and western medicine more effective, medical institutions should optimize the management mode of specialist nurses around the following nine aspects: strictly employing specialized nurses, setting up standardized posts of specialized nurses, formulating and perfecting the work and assessment system, establishing specialist nursing team, strengthening humanized management, optimizing outpatient layout, strengthening patient education, optimizing the process of seeing a doctor, and establishing outpatient nursing supervision group. (专科护士在中西医结合门诊护理中发挥着重要作用。本文从严格聘任用专科护士、设置规范化专科护士岗位、制定完善工作及考核制度、建立专科护理团队、加强人性化管理、优化门诊布局、加强患者宣教、优化就诊流程、建立门诊护理监督小组9个方面总结了优化专科护士管理模式的实践经验, 以为实现中西医结合门诊护理更大的效益提供参考。)

Clear cell renal carcinoma (ccRCC) is histologically defined by its cytoplasmic lipid deposits. Lipid metabolism disorder largely increases the risk of ccRCC. In this study, we aimed to investigate the biological functions and molecular mechanisms of carnitine palmitoyl transferase 1A (CPT1A) in ccRCC. Our results showed that CPT1A is decreased in ccRCC clinical samples and cell lines compared with that in normal samples. Lentivirus overexpressing CPT1A was used to investigate the neoplastic phenotypes of ccRCC, and the results showed that lipid accumulation and tumor growth are attenuated both in vitro and in vivo. In addition, CPT1A prevents cholesterol uptake and lipid accumulation by increasing the peroxisome proliferator-activated receptor α (PPARα) level through regulation of Class B scavenger receptor type 1 (SRB1) and cluster of differentiation 36 (CD36). Furthermore, PI3K/Akt signaling pathway promotes tumor cell proliferation in ccRCC, which is related to the enhanced expression of CD36. Functionally, weakened CPT1A expression is critical for lipid accumulation to promote ccRCC development. Collectively, our research unveiled a novel function of CPT1A in lipid metabolism via PPARα/CD36 axis, which provides a new theoretical explanation for the pathogenesis of ccRCC. Targeting CPT1A may be a potential therapeutic strategy to treat ccRCC.

In order to avoid the tunneling disasters in the adverse geology, the ultra-high performance concrete needs to be used for control the deformation. As a random multiphase material, concrete is mostly heterogeneous and heterogeneous, and its characteristics are complex. So the relevant test cycle is long and the cost is high. In order to know the required mechanical properties of the ultra-high performance concrete, the advanced research can be carried out by the finite element method. The fiber-reinforced concrete model was established to study how the multi-scale hybrid fiber-reinforced concrete has been enhanced by the finite element method. The concrete is considered as the elastic-plastic constitutive relationship, but the fibers in the concrete follow the elastic constitutive relationship. Eight-node hexahedral reduced integral elements are adopted for both matrix and fiber. The reliability and validity of the fiber-reinforced ultra-high performance concrete by the finite element method was verified by the experiment. It can be used to predict the mechanical properties of concrete with different fiber characteristics, but unable to be used to predict more complex behaviors such as damage and fracture. The results indicate that the compressive strength and the flexural strength of concrete with a fiber volume content of 1.0% are larger than other 6 different fiber volume content, the beam axially undergoes plastic deformation is the largest of the seven, and the fiber concrete numerical model can better simulate the static mechanical properties and the failure mechanism of fiber fibers when the fiber volume content is 0.1%, and the fiber length is 15 mm. This study can provide a reasonable and effective reference for the actual engineering.

Aiming at the problem of gas emission in roadway driving of crushed soft coal seam in the Sangshuping No.2 Coal Mine, the key technologies of comb type directional long drilling are studied such as the hole arrangement way, branch hole spacing, construction process, track control, branch measurement drilling and original hole reentry, and a set of key technologies of forward comb type directional drilling techniques suitable for drilling cover excavation of pre-driving roadways are formed. The field application shows that the technologies can effectively solve the problems of low pore formation rate, low trajectory control accuracy and high construction accident rate, and provide the reliable channel for the successful implementation of hydraulic fracturing technology.

Abstract The lungs and skin are important respiratory organs in Anura, but the pulmonary structure of amphibians remains unclear due to the lack of a suitable procedure. This study improved the procedure used for fixing lungs tissues and used light microscopy, transmission electron microscopy and scanning electron microscopy to reveal the differences in the lung and skin morphologies between Pelophylax nigromaculatus (P. nigromaculatus) and Bufo gargarizans (B. gargarizans). In P. nigromaculatus and B. gargarizans, the cystic lungs comprise a continuous outer pulmonary wall on which primary, secondary, and tertiary septa attach, and a number of regular lattices form from raised capillaries and the pulmonary epithelium on the surfaces of the pulmonary wall and septa. Each lattice in P. nigromaculatus consists of several elliptical sheets and flat bottom, and the septa are distributed with denser sheets and have a larger stretching range than the pulmonary wall. The lattice in B. gargarizans consists of thick folds and an uneven bottom with several thin folds, and the septa have more developed thick and thin folds than the pulmonary wall. However, the density of the pulmonary microvilli, the area of a single capillary, the thicknesses of the blood-air barrier, pulmonary wall and septum, and the lung/body weight percentage obtained for B. gargarizans were higher than those found for P. nigromaculatus. In P. nigromaculatus, the dorsal skin has dense capillaries and a ring surface structure with mucus layer on the stratum corneum, and the ventral skin is slightly keratinized. In B. gargarizans, the stratum corneum in both the dorsal and ventral skins is completely keratinized. A fine ultrastructure analysis of P. nigromaculatus and B. gargarizans revealed that the pulmonary septa are more developed than the pulmonary walls, which means that the septa have a stronger respiratory function. The more developed lungs are helpful for the adaptation of B. gargarizans to drought environments, whereas P. nigromaculatus has to rely on more vigorous skin respiration to adapt to a humid environment.

The “five-aquifer” occurrence conditions of Zhuxianzhuang Coal Mine are complex, and there are some water disaster characteristics such as large static reserves, strong dynamic supply and high water pressure, which seriously threatens the mine safety production. The water damage governance method of “curtain closure and drainage mining” is adopted, and the ground grouting drilling technology is the basis for this method implementation. Combined the technical parameters of geological conditions, drilling technology and grouting technology, the drilling equipment, construction technology, casing solid completion technology and trajectory control technology of ground grouting well are systematically studied, and a set of drilling equipment and key technologies for the ground grouting well of Zhuxianzhuang Coal Mine are formed. The field application shows that the drilling equipment and technology are safe and reliable, energy-saving and environmentally-friendly, the grouting effect is good.

Ground grouting technology is effective method to prevent and control coal mine water hazard, and grouting multi-branch horizontal well is the foundation of ground grouting technology. Combined the characteristics of geological conditions, drilling techniques and grouting techniques, the truck-mounted drilling rig, rare-earth permanent magnet direct drive mud pump, EMWD and solid control system were selected, which were suitable for grouting well. The key technologies such as drilling structure, trajectory control, casing construction were studied. A set of drilling equipment and key technologies for grouting multi-branches horizontal well was formed, it had great significance to prevent and control water hazard in coal mines.

In order to meet the construction requirements of CBM horizontal well and reduce the drilling cost, it is necessary to investigate and summarize the conventional water-source drilling rig, oil drilling rig and truck-mounted drilling rig. Combined with the characteristics of geological conditions, operating environment and construction technology of CBM horizontal well, the fully hydraulic truck-mounted drilling rig is selected, which was suitable for CBM horizontal well. The characteristics of conventional mud pump group are analyzed, the 150 kW energy-saving generator is connected in parallel at the output of diesel engine, and the mud pump group is optimized. Based on the conventional oil solid control system, a four-stage solid control system for CBM horizontal well is designed. Thus, a set of drilling equipment for CBM horizontal well is formed.

With 20% sweet potato puree and wheat flour as raw materials, the effects of knead times,fermentation time and fermentation temperature on the quality of sweet potato puree steamed bread were studied.On the basis of single factor test, sensory evaluation was selected as the evaluation index, and response surface analysis was used to optimize the processing technology of sweet potato puree steamed bread.The results showed that the optimum technological formula of sweet potato puree steamed bread was as follows： 14 times of kneading, 18 min of fermentation and 33 ℃ of fermentation temperature.With special sweet potato flavor, the quality of sweet potato puree steamed bread is better under this condition.

In a boundary layer ingestion (BLI) propulsion system, the compressor rotor operates under the condition of a severe inflow distortion because the boundary layers on the surface of aircraft have been ingested. In this situation, the low-momentum fluid would inevitably raise the blade load and aggravate the local aerodynamic losses, thus severely deteriorating the compressor overall aerodynamic performance. The paper has applied a sweep optimization design based on surrogate model and genetic algorithm to a transonic axial-flow compressor at the condition of total pressure distorted inflow. The optimization objective is to improve the compressor efficiency. The sweep design has been implemented through controlling the shape of the blade stacking line and the time-saving steady numerical simulations are mainly utilized in the optimization process. Then, the full-annulus unsteady CFD calculations have been conducted for validating the optimized design and further analyzing the flow mechanisms of performance improvements. The computational results show that the inflow distortion has led to non-uniform distributions of the tip leakage loss and the hub flow separation loss along the circumferential direction. It is found that the rotor blade has suffered from the highest tip leakage losses and hub separation losses during the blade leaving the distorted region. After rotor sweep optimization, both tip leakage and hub separation losses have been notably reduced along the full circumferential direction. Moreover, for different pitchwise locations, the optimized rotor sweep design has achieved more aerodynamic performance improvements in the process of the rotor blade leaving the distorted region than those in the processes of the rotor blade moving out of, moving towards and entering the distorted region. Overall, the optimized design performs better than the baseline design in terms of adiabatic efficiency in the entire operating range. In the meanwhile, the total pressure ratio has been maintained. Specifically, an approximately 0.5% increment of efficiency has been achieved by the optimized design at the optimization point. For this paper, the major purpose is to offer useful guidelines for fan/compressor design strategy to achieve high aerodynamic performances under distorted inflow working condition.

The domestication of the yak on the Qinghai–Tibetan Plateau probably dates back to 7300 years ago, when the rangelands were also utilized for cultivation. Over time, a complete system of herding and rangeland management developed. In recent years, however, the rangeland contract policy and nomadic settlement project have reduced the mobility of herds through the decollectivization of the rangeland. This process has destroyed the traditional nomadic lifestyle and caused difficulties, forcing the herders to adapt to new ways. This paper considers 3 issues: (1) the implementation of the contract policy and the settlement project—2 important policies that have caused the decollectivization of rangeland on the Qinghai–Tibetan Plateau; (2) the effects of the 2 policies on herding at 2 sites; and (3) the adaptive strategies employed by herders against the constraints of the policies. The study incorporates a literature review, fieldwork, key-person interviews, and focus group discussions. Community-based self-management of the rangeland appears to be the best strategy for herders. Policies such as group herding can help herders increase herd mobility, which is crucial for sustainably raising livestock on the Qinghai–Tibetan Plateau.

The surface and micro-interface property of three domestic 800-grade carbon fibers (1#, 2#, 3#) were characterized by Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM), X-ray Photoelectron Spectroscopy (XPS), multifilament stretching method and single fiber fragmentation test. The results show that the surfaces of these three fibers are all smooth and the roughness is between 9-17nm. They all possess high content of oxygen, and the ratio of O/C of the three carbon fibers is between 0.23-0.27. The multifilament tensile property is similar, which reveals the domestic carbon fibers have stable quality control, and the breaking elongation rate of about 1.9 revealing that the fiber and resin matrix matching is good. The tensile strength of single fiber is unstable, meanwhile the high tensile surface active functional group has big influence on the interface shear strength of carbon fibers.

Eco-tourism is a major trend in the development of the world’s tourism industry and a crucial part of Chinese tourism industrial restructuring. The development of eco-tourism should start with the management of eco-tourism. This article mainly discusses the management innovation of tourism enterprises under the eco-tourism model, summarizes the current situation of eco-tourism development, puts forward the problems in the management of tourism enterprises under the eco-tourism model, and finally puts forward suggestions about that, in order to promote the development of tourism enterprise management.