Investigating spatio-temporal variations and contributing factors of land use-related carbon emissions in the Beijing-Tianjin-Hebei Region, China.

The land use change is the primary factor in influencing the regional carbon emissions. Studying the effects of land use change on carbon emissions can provide supports for the development policies of carbon emission. Using land use and energy consumption data, this study measures carbon emissions from land use dynamics in the Beijing-Tianjin-Hebei region from 2000 to 2020. The standard deviation ellipse model is employed to investigate the distribution characteristics of the spatial patterns of carbon emissions, while the Geographically and Temporally Weighted Regression (GTWR) model is used to examine the contributing factors of carbon emissions and their spatial and temporal heterogeneity. Results indicate a consistently increasing trend in carbon emissions from land use in the Beijing-Tianjin-Hebei region from 2000 to 2020. Construction land is characterized with both the primary source and an increasing intensity of carbon emissions. Besides, the spatial distribution of carbon emissions from land use in the Beijing-Tianjin-Hebei region demonstrates an aggregation pattern from in the northeast-southwest direction towards the center, with a greater aggregation trend in the east-west direction compared to that in the south-north direction. During the study period, a positive correlation was documented between carbon emissions and factors including total population, economic development level, land use degree, and landscape patterns. This correlation showed a decreasing trend and reached a stable level at the end of the study period. Moreover, the analysis showed a negative correlation between industrial structure and carbon emissions, which showed an increasing trend and reached a relatively high level at the end of the study period.

Hyperspectral Characteristics and SPAD Estimation of Wheat Leaves under CO2 Microleakage Stress.

To non-destructively and rapidly monitor the chlorophyll content of winter wheat leaves under CO2 microleakage stress, and to establish the quantitative relationship between chlorophyll content and sensitive bands in the winter wheat growing season from 2023 to 2024, the leakage rate was set to 1 L/min, 3 L/min, 5 L/min, and 0 L/min through field experiments. The dimensional reduction was realized, fractional differential processing of a wheat canopy spectrum was carried out, a multiple linear regression (MLR) and partial least squares regression (PLSR) estimation model was constructed using a SPA selection band, and the model's accuracy was evaluated. The optimal model for hyperspectral estimation of wheat SPAD under CO2 microleakage stress was screened. The results show that the spectral curves of winter wheat leaves under CO2 microleakage stress showed a "red shift" of the green peak and a "blue shift" of the red edge. Compared with 1 L/min and 3 L/min, wheat leaves were more affected by CO2 at 5 L/min. Evaluation of the accuracy of the MLR and PLSR models shows that the MLR model is better, where the MLR estimation model based on 1.1, 1.8, 0.4, and 1.7 differential SPAD is the best for leakage rates of 1 L/min, 3 L/min, 5 L/min, and 0 L/min, with validation set R2 of 0.832, 0.760, 0.928, and 0.773, which are 11.528, 14.2, 17.048, and 37.3% higher than the raw spectra, respectively. This method can be used to estimate the chlorophyll content of winter wheat leaves under CO2 trace-leakage stress and to dynamically monitor CO2 trace-leakage stress in crops.

Maxingxiongting mixture attenuates hypoxia pulmonary arterial hypertension to improve right ventricular hypertrophy by inhibiting the rho-kinase signaling pathway.

OBJECTIVE: To explore the mechanism of Maxingxiongting mixture (MXXTM) on pulmonary hypertension in a rat model established by intraperitoneal injection of monocrotaline solution, smoking and forced swimming. METHODS: A total of 30 male Sprague-Dawley rats were randomly divided into five groups: control group, model group, high-dose of MXXTM group (HM), low-dose of MXXTM group (LM), and fasudil group. The mean pulmonary artery pressure (mPAP) was measured by using a miniature catheter. Lung tissue and right ventricular tissue sections were stained with hematoxylin-eosin. The right ventricle (RV) and left ventricle + septum (LV + S) were weighted. RV/(LV+S) was calculated to reflect the degree of right ventricular hypertrophy. Rho/Rho-kinase signaling pathway key proteins (RhoA, ROCK Ⅰ and ROCK Ⅱ) in rat right ventricular tissue were measured by Western blot analysis. The levels of serum hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and the levels of plasma renin activity (PRA), angiotensin Ⅱ (ANG-Ⅱ), aldosterone (ALD) in rat anticoagulated plasma were all measured by enzyme-linked immunosorbent assay. RESULTS: Compared with the control group, the mPAP and RV/(LV+S) in the model group were significantly increased. Administration of fasudil resulted in a significant decrease of mPAP and RV/ (LV+S). In the HM group and LM group, mPAP and RV/ (LV+S) were significantly lower than the model group. Compared with the control group, the contents of HIF-1α, VEGF, PRA, ANG-Ⅱ and ALD in the model group were significantly increased. The administration of fasudil and high-dose MXXTM significantly reduced the contents of HIF-1α, VEGF, PRA, ANG-II and ALD. Compared with the control group, the expression of RhoA, ROCK Ⅰ and ROCK Ⅱ in the right ventricle of the model group were significantly increased. The administration of fasudil and high-dose MXXTM significantly reduced the expression of RhoA and Rock Ⅱ proteins. Our results indicated that high-dose of MXXTM had similar effects on reducing pulmonary artery pressure and improving right ventricular remodeling to fasudil. However, MXXTM was unable to restore parameters above to control levels. CONCLUSIONS: MXXTM attenuates hypoxia pulmonary arterial hypertension to improve right ventricular hypertrophy by inhibiting the Rho-kinase signaling pathway.