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The ecosystem apparent quantum yield (α), maximum rate of gross CO2 assimilation (P max) and daytime ecosystem respiration rate (R d), reflecting the physiological functioning of ecosystem, are vital photosynthetic parameters for the estimation of ecosystem carbon budget. Climatic drivers may affect photosynthetic parameters both directly and indirectly by altering the response of vegetation. However, the relative contribution and regulation pathway of environmental and physiological controls remain unclear, especially in semi-arid grasslands. We analyzed seasonal and interannual variations of photosynthetic parameters derived from eddy-covariance observation in a typical semi-arid grassland in Inner Mongolia, Northern China, over 12 years from 2006 to 2017. Regression analyses and a structural equation model (SEM) were adopted to separate the contributions of environmental and physiological effects. The photosynthetic parameters showed unimodal seasonal patterns and significantly interannual variations. Variations of air temperature (T a) and soil water content (SWC) drove the seasonal patterns of photosynthetic parameters, while SWC predominated their interannual variations. Moreover, contrasting with the predominant roles of T a on α and R d, SWC explained more variance of P max than T a. Results of SEM revealed that environmental factors impacted photosynthetic parameters both directly and indirectly through regulating physiological responses reflected by stomatal conductance at the canopy level. Moreover, leaf area index (LAI) directly affected α , P max and R d and dominated the variation of P max. On the other hand, SWC influenced photosynthetic parameters indirectly through LAI and canopy surface conductance (gc). Our findings highlight the importance of physiological regulation on the photosynthetic parameters and carbon assimilation capacity, especially in water-limited grassland ecosystems. [ABSTRACT FROM AUTHOR]

Beijing, as the capital of China, suffers severe subsidence caused by groundwater withdrawal. In this paper, the SBAS-InSAR technique was used to detect surface deformations in the Beijing plain. 47 scenes Envisat ASAR images obtained during June 2003 to August 2010, and 24 Radarsat-2 images obtained during November 2010 to December 2013 were employed to retrieve vertical deformation characteristic over this area. The deformation magnitude, evolution process and spatial distribution of representative targets that occurred during 11 years were retrieved. The vertical surface displacement rates during two periods were validated via leveling observations, which have an RMSE =1.15mm/a, which indicates that the two types of subsidence matched very well. The interferometric results revealed that the subsidence during the two periods show similar special distributions and have an uneven spatial-temporal trend. The scope and deformation rates of funnels continuously increased with from 2003 to 2013. Meanwhile, multiple expressways and urban ring roads spanned the subsidence funnel with sharp deformation rate, and showed different subsidence properties along their paths. Additionally, the spatial and temporal correlation analyses between the deformation measurements and the dynamic variation of groundwater pumping was also performed to explore the response relationship. [ABSTRACT FROM AUTHOR]

• Energy partitioning regime transferred from H- to LE-dominated along the aridity gradient. • The role of vegetation in energy partitioning was strengthened from desert to meadow steppes. • Response of β to climate and vegetation factors was more sensitive with increasing aridity. Surface energy exchange is vital because it affects microclimate, water cycle and biogeochemical processes in the canopy-atmosphere interface. In this study, seasonal variations and regulators of energy fluxes and partitioning were investigated based on a long-term eddy flux observation dataset (12 towers, 82 site-years in total) along an aridity gradient in temperate grasslands of Northern China. Our results showed that the net radiation (R n) and all energy components, including latent heat (LE), sensible heat (H) and ground heat (G 0) fluxes, presented unimodal seasonal patterns across different grassland types, with R n and LE peaked in the middle growing season but H and G 0 at the beginning of the growing season. The energy partitioning shifted from the H-dominated to the LE-dominated period accompanied vegetation phenological development, thus a U-shaped seasonal pattern of Bowen ratio (β, H/LE) was observed. Prolonged LE-dominated period and great peak of LE flux enhanced LE/R n proportion and decreased β from desert steppes to typical steppes and meadow steppes. Climate and vegetation factors co-regulated the seasonal patterns of energy fluxes and partitioning, with enhanced effects of LAI and canopy surface conductance (g c) from desert steppes to typical and meadow steppes, but a reverse pattern of land-atmosphere coupling via vegetation physiological regulation. Meanwhile, enhanced sensitivity of β in response to variations of climate and vegetation factors was also observed with increasing aridity. Our founding highlighted the role of vegetation especially physiological regulation in determining the seasonal patterns of energy fluxes and partitioning in water-limited grasslands. Whereas, the great sensitivity of energy partitioning to vegetation changing with increasing aridity also emphasized that it is vital to pay attention to the response of energy exchange in the desert steppes to the greening trend in Northern China under future climate scenarios. [ABSTRACT FROM AUTHOR]

Quantifying the variation of forest transpiration (T) is important not only for understanding the water and energy budget of forest ecosystems but also for the prediction, evaluation, and management of hydrological effects as well as many other ecosystem services of forests under the changes of climate, vegetation, and anthropological impacts. The accurate prediction of T, a key component of water used by forests, requires mechanism-based models describing the T response to environmental and canopy conditions. The daily T of a larch (Larix principis-rupprechtti) plantation was measured through monitoring the sap flow in the growing season (from May to September) of a dry year (2010), a normal year (2012), and a wet year (2014) at a shady slope in the semi-arid area of Liupan Mountains in northwest China. Meanwhile, the meteorological conditions, soil moisture, and forest canopy leaf area index (LAI) were monitored. To get a simple and easily applicable T model, the numerous influencing parameters were grouped into three factors: the atmospheric evapotranspiration demand indicated by the potential evapotranspiration (PET), the soil water supply ability indicated by the relative extractable soil water content (REW), and the vegetation transpiration capacity indicated by the forest canopy LAI. The T model was established as a continuous multiplication of the T response equations to individual factors, which were determined using the upper boundary lines of measured data. The effect of each factor on the T in a dry year (2010) or normal year (2012) was assessed by comparing the measured T in the baseline of the wet year (2014) and the model predicted T, which was calculated through inputting the actual data of the factor (i.e., PET) to be assessed in the dry or normal year and the measured data of other two factors (i.e., REW, LAI) in the baseline of the wet year. The results showed that the mean daily T was 0.92, 1.05, and 1.02 mm; and the maximum daily T was 1.78, 1.92, and 1.89 mm in 2010, 2012, and 2014, respectively. The T response follows a parabolic equation to PET, but a saturated exponential equation to REW and LAI. The T model parameters were calibrated using measured data in 2010 and 2012 (R2 = 0.89, Nash coefficient = 0.88) and validated using measured data in 2014 satisfactorily (R2 = 0.89, Nash coefficient = 0.79). It showed a T limitation in the dry year 2010 for all factors (18.5 mm by PET, 11.5 mm by REW, and 17.8 mm by LAI); while a promotion for PET (1.4 mm) and a limitation for REW (4.2 mm) and LAI (14.3 mm) in the normal year 2012. The daily T model established in this study can be helpful to assess the individual factor impact on T and improve the daily T prediction under changing environmental and canopy conditions. [ABSTRACT FROM AUTHOR]

The rock drilling and blasting method is the most commonly adopted method for rock roadway excavation in China, where cutting efficiency is the key factor affecting the excavation speed. The conventional wedge-shaped cut blasting is not suitable for deep hole blasting since the method requires the explosives to be concentrated at the bottom of the borehole, resulting in uneven fragmentation of the upper rock and difficulty in throwing the bottom rock. In addition, the cut area is small, and the range of cavity created after cut hole blasting cannot meet the needs of large section blasting tunneling. This present study proposes an efficient method for charging and detonation inside and between boreholes called disperse charge and staged detonation (DCSD) cut blasting technique. The DCSD cut blasting and traditional wedge cut blasting models were established and compared using the smooth particle hydrodynamics-finite element method (SPH-FEM). The results shows that the DCSD model reduces the minimum resistance line of rock blasting and creates a new free surface, promoting the throwing of the bottom rock mass and the overall rock mass failure. Furthermore, the cutting efficiency is defined to quantitatively analyze the influence of different parameters on the cutting effect. The cutting efficiency of the DCSD model with dispersed charge is 21.89% higher than that of the blasting model with continuous charge. The cutting effect is at its greatest for the three types of ε designed for the study, when ε = 0.5. The increase in hole depth reduces the cutting efficiency marginally, although it is still higher than that in the traditional mode. Finally, the successful application of digital electronic detonator and DCSD in domestic rock roadway blasting construction verifies the applicability of DCSD and provides a reference for subsequent projects involving rock roadway deep hole drilling and blasting construction. [ABSTRACT FROM AUTHOR]

Abstract: Late Mesozoic large-scale crustal extension occurred across the northeastern section of continental Asia, and metamorphic core complexes (MCCs) are the major features in this region. This paper presents new zircon U–Pb and Ar–Ar ages of biotite and hornblende for pre- or syn- (mylonitized) and post-kinematic (unmylonitized) intrusions from these MCCs, and attempts to determine the timing of initiation, duration and termination of the mid-lower-crustal ductile extension by integrating with geochronological data from previous studies. These MCCs have similar 40Ar/39Ar biotite and hornblende ages (130 to 110Ma, mainly from 130 to 120Ma), which are interpreted as the cooling ages and represent the timing of the late-stage formation of the MCCs. Zircon U–Pb ages for syn- to post-kinematic intrusions from some MCCs suggest that the mid-lower-crustal extension probably initiated at ca. 150–145Ma with a peak occurring 145–130Ma and continued to 130–120Ma, which is older than that suggested by 40Ar/39Ar ages by 10–20Ma. The early ductile extension most likely initiated in Mongolia and northern China during the Late Jurassic (150–145Ma) at a deeper level, then propagated southwards (140–130Ma), and finally developed throughout the entire continental NE Asia (130–120Ma). Based on the timing and processes of the extension, a geodynamic model and tectonic setting of the destruction of the North China Craton (NCC) are proposed. [Copyright &y& Elsevier]

• Soil water balance in SWAT is modified with subsurface flow exchange between HRUs. • Subsurface flow affects soil water availability through water storage capacity. • Subsurface flow redistribution shapes convex spatial pattern of LAI. Soil water-vegetation interactions have been a research topic for decades. Landscape patterns can be shaped by soil water availability, and in reverse. The effects of subsurface flow on the soil water – vegetation interactions are relatively less studied than the surface flow, especially in the semiarid region. This work is focused on how the larch (Larix principis-rupprechtti) interacted with soil water, and how the convex pattern of the larch was formed along the stony soil slope in the semiarid Loess Plateau, northwest China. The soil water balance equation in Soil Water Assessment Tool (SWAT) was modified to include subsurface flow exchange between two adjacent hydrologic response units (HRUs). The slope was then delineated into adjacent HRUs to understand the hydrologic and ecological processes inside the slope. The modified SWAT model on the slope was calibrated and validated by the field data. The model was forced by a 55-year meteorological data series to investigate the larch-soil water interactions and the formation of the convex distribution pattern over long term. It is found that the subsurface flow has shaped the convex distribution of vegetation LAI along the slope. The subsurface flow occurs due to relatively high permeability of the stony soil, and it affects the heterogeneities of soil water availability through the soil water storage capacity. The concave spatial pattern of the soil water stress determines the vegetation growth along the slope in this semiarid region. These understandings provide new knowledge about the influences of hydrological processes on vegetation distribution patterns along a slope, which is useful in vegetation management under similar conditions. [ABSTRACT FROM AUTHOR]

In this study, medium roasted coffee with four different fermented coffee fruits post-treatments (dry, wet, semi-dry and hot air dry) was used as the material. Chemical profile and sensorial analysis were used to comprehensively analyze the effects of post-treatments on coffee flavor characteristics from multiple dimensions. A total of 31 water-soluble chemical components and 39 volatile compounds were identified in roasted coffee, and distinct post-treatments based on chemical orientation make coffee highly differentiated. In addition, the principal component analysis (PCA) of the chemical composition integrated data set showed that the first two principal components could explain 54.9% of the sample variability. All four post-treatments can be classified as "specialty coffees" according to the Specialty Coffee Association (SCA) protocol, with various organoleptic characteristics and flavor attributes. As a result, the fermented coffee fruits post-treatment method further determines the quality characteristics of coffee, thus meeting the needs of different niche markets., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

BACKGROUND Ropivacaine is commonly used as an intercostal nerve block, but its effects on postoperative cognitive dysfunction (POCD) have not previously been investigated. This study aimed to examine the effects of the use of ropivacaine as an intercostal nerve block on early POCD, postoperative analgesia, and inflammation in patients following thoracotomy for esophageal cancer. MATERIAL AND METHODS One hundred patients with esophageal cancer undergoing thoracotomy were randomly divided into a group with intercostal nerve block (group A) (n=50) and a control group (group B) (n=50). The cognitive function score and visual analog scale (VAS) scores for pain were measured at one hour before surgery (T1), two hours after surgery (T2), 12 hours after surgery (T3), and 24 hours after surgery (T4). Blood samples were collected at each time point, and plasma levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), IL-10, and S100-β were measured using an enzyme-linked immunosorbent assay (ELISA). Cognitive function was determined using the Mini-Mental State Examination (MMSE) scale. RESULTS The VAS scores in group A were significantly lower compared with group B (p<0.05). In the T2, T3, and T4 time points, group A had significantly increased MMSE scores compared with group B (p<0.05). Compared with group B, the levels of IL-6 and TNF-a were significantly decreased in group A at T3 and T4 (p<0.05), while the levels of IL-10 were significantly increased (p<0.05) when compared with group A. CONCLUSIONS The use of the intercostal nerve block, ropivacaine, improved early PCOD in patients following thoracotomy for esophageal cancer.

Highly active antiretroviral therapy can reduce the human immunodeficiency virus (HIV) viral load in the plasma to undetectable levels. However, because of the presence of latent HIV reservoirs, it is difficult to completely eradicate HIV in infected patients. Our objective was to assess the potency of chidamide, a novel histone deacetylase inhibitor recently approved for cancer treatment by the China Food and Drug Administration, to reactivate latent HIV-1 via histone acetylation. Viral reactivities of chidamide were accessed in 2 latent HIV pseudotype virus cell reporter systems (J-Lat Tat-green fluorescent protein clone A72 and TZM-bl), a latently infected full-length HIV virus cell system (U1/HIV), and resting CD4 + T cells from 9 HIV-infected patients under highly active antiretroviral therapy with undetectable viral load. Chidamide was able to increase HIV expression in each cell line, as evidenced by green fluorescent protein, luciferase activity, and p24, as well as to reactivate latent HIV-1 in primary CD4 + T cells of HIV-infected patients. Histone acetylation adjacent to the HIV promoter in A72 cells was determined by chromatin immunoprecipitation. Chidamide was able to increase histone H3 and H4 acetylation at the HIV promoter. In brief, chidamide induced the reactivation of latent HIV in pseudotype virus reporter cells, latently infected cells, and primary CD4 + T cells, making this compound an attractive option for future clinical trials., (© 2018 Wiley Periodicals, Inc.)