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[Objective] The major function-oriented zones (MFOZs) play a strategic role in promoting the coordinated development of population, economy, society, resources, and environment. In response to the emerging trend of population shrinkage and more compact development of cities, it is necessary to review and evaluate the implementation of MFOZ and propose optimization suggestions. [Methods] This study used census and land survey data to explore the spatiotemporal patterns of population-land growth/shrinkage in counties of Hunan Province. It quantitatively analyzed the coordination between population and land from 2010 to 2020. Comparing the results with objectives set in the Hunan Province MFOZ Plan (2012), it summarized the characteristics of population-land changes under the MFOZ framework, which led to discussions on the future optimization direction of MFOZ. [Results] The study found that: (1) From 2010 to 2020, there were obvious differentiated development pathways of urban population growth/shrinkage in various counties of Hunan Province. Overall, urban land showed a growing trend, but the growth rate declined. (2) There was a widespread of population-land imbalance in the counties from 2010 to 2020. Many counties exhibited two mismatch trends: more population and less land (compact development), and less population and more land (expansive development). Both the counties with urban population growth lagging behind urban construction land growth and those with urban population growth slightly faster than urban construction land growth were observed. (3) Since its implementation in Hunan Province in 2012, although the MFOZ Plan has played the role of guiding coordinated development of population and land, there are still situations where the results are inconsistent with the development goals of the MFOZ. [Conclusion] Based on the analysis, this study explored optimization solutions for the MFOZ. On the one hand, from the perspective of population-land coordination, various types of MFOZ (urbanization areas, major agricultural production areas, and key ecological function areas) may have multiple development scenarios, and it is necessary to further refine their classification and propose multi-type development directions for Hunan Province. On the other hand, there is a bidirectional mechanism of influence between MFOZ types and urban land, as well as urban population. Future MFOZ planning needs to combine the population-land growth relationship derived from data analysis and propose optimization paths from the perspective of coordinated development between the two.

As a biomedical material，TC4 titanium alloy is widely used in the field of bone tissue repair in clinical practice，with annual consumption of about one million pieces in China.However，the properties of TC4 titanium alloy as low wear resistance and poor biological activity seriously restricted its expansion in engineering application.Therefore，a micro-arc oxidation/hydrothermal coating on surface of TC4 was fabricated by utilizing the micro-arc oxidation/hydrothermal synthetic composite technology，and the effects of La(NO3)3 doping amount in the hydrothermal synthesis solution on the phase composition，micro morphology，microhardness，wear resistance and other parameters of the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy were surveyed.Moreover，the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy was characterized by XRD，SEM，microhardness tester and friction and wear testing machine.Results showed that the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy was mainly composed of anatase TiO2 and hydroxyapatite.After hydrothermal treatment，La3+ in the synthetic solution entered the composite coating and participated in the coating reaction.With the increase of La(NO3)3 doping amount，the content of hydroxyapatite phase in the composite coating increased first and then decreased.When the doping amount of La(NO3)3 exceeded 24 mmol/L，the coating surface became smoother.In addition，the microhardness of micro-arc oxidation/hydrothermal composite coating on TC4 titanium alloy decreased first and then increased，and the friction coefficient increased first and then decreased.As the doping amount of La(NO3)3 reached 24 mmol/L，microhardness of the composite coating on TC4 titanium alloy acquired the minimum value，and it was about (271.8±3.1)HV9.8 N，the friction coefficient of the composite coating obtained the maximum value，and it was about 0.8～0.9.

Abstract Aim To explore the effects of hypothermia and hypoxia on rat skeletal muscle and lipid metabolism. Method Forty male rats were randomly divided into blank group, low-temperature group, hypoxia group, and hypothermia combined with hypoxia group. The body weight of the rats was monitored. The changes of Irisin were detected by ELISA, and LDL, HDL, TC, and TG levels in serum were detected by blood biochemistry. Western blot was used to detect the changes of lipid metabolism-related proteins. CCK8 was used to verify the effect of AMPK/PGC1α on the proliferation of rat skeletal muscle cells. Result In the case of cold stimulation and hypoxia, the weight of the rats decreased significantly, and the levels of LDL, HDL, TC, and TG in the serum were abnormal. The activity of fatty acid metabolism factors Irisin, UCP-1, and FABP4 is down-regulated by hypothermia and hypoxia. The activity of fat metabolism-related enzymes, ATGL, HSL, and MGL increased under hypothermia and low oxygen conditions. Hypothermia and hypoxia affected the morphology of skeletal muscle, and AMPK/PGC-1α can regulate the proliferation of skeletal muscle cells. Conclusion Hypothermia and hypoxia can reduce the body weight of rats, and affect the structure of skeletal muscle to promote lipid metabolism through AMPK/PGC-1α signaling pathway.