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The biogas production (BP), volatile fatty acids (VFAs), microbial communities, and microbes' active enzymes were studied upon the addition of biochar (0–1.5%) at 6% and 8% slaughterhouse waste (SHW) loadings. The 0.5% biochar enhanced BP by 1.5- and 1.6-folds in 6% and 8% SHW-loaded reactors, respectively. Increasing the biochar up to 1.5% caused a reduction in BP at 6% SHW. However, the BP from 8% of SHW was enhanced by 1.4-folds at 1.5% biochar. The VFAs production in all 0.5% biochar amended reactors was highly significant compared to control (p- value < 0.05). The biochar addition increased the bacterial and archaeal diversity at both 6% and 8% SHW loadings. The highest number of OTUs at 0.5% biochar were 567 and 525 in 6% and 8% SHW, respectively. Biochar prompted the Clostridium abundance and increased the lyases and transaminases involved in the degradation of lipids and protein, respectively. Biochar addition improved the Methanosaeta and Methanosphaera abundance in which the major enzymes were reductase and hydrogenase. The archaeal enzymes showed mixed acetoclastic and hydrogenotrophic methanogenesis. [Display omitted] • Maximum biogas production in all SHW loadings was achieved at 0.5% biochar. • The core microbes in all reactors were Clostridium (>45%) and Methanosaeta (>40%). • Lyases and transaminases were the major bacterial enzymes for SHW-digestion. • Reductase and hydrogenase were the core archaeal enzymes for biogas production. [ABSTRACT FROM AUTHOR]

By integrating the reflectance of 7 spectral bands of the MODerate-resolution Imaging Spectroradiaometer (MODIS) and forest inventory data with an empirical statistical model, we mapped the spatial distribution of total forest biomass carbon density (BCD) at 1 km resolution in China during the past decade. The empirical statistical model can explain 75% of the variation in BCD across 29 provinces in China ( R 2 = 0.75, P < 0.001), with a root mean square error of 9.3 Mg C ha −1 . The total forest biomass carbon storage was estimated as 6.4 ± 0.6 Pg C, with an average BCD of 42.6 ± 3.9 Mg C ha −1 during the period of 2001–2005, which is close to the estimates solely by forest inventory data. During the 2000s, the forests in China sequestered carbon by 80 ± 103 Tg C yr −1 . Our estimation is close to an independent forest biomass estimation (76 ± 10 Tg C yr −1 ) derived from passive microwave satellites (Liu et al., 2015). Most of the forest biomass carbon sink was attributed to the growth of low- and medium-biomass forests in eastern, central, and southern China. The large area of currently low-biomass forests will retain as a large potential biomass C sink in the next few decades. This implicates that low-biomass forests (most of these forests are planted forests) need well management such as selected wood harvest to keep large forest biomass carbon sinks in China. Plans of sustainable afforestation and forests protection projects by Chinese government could also enhance the forest biomass carbon sinks in the future. Nitrogen deposition in China significantly correlates with forest biomass C sinks across 2392 0.5° × 0.5° grid cells ( R = 0.54, P < 0.001), which indicate the positive impacts of nitrogen deposition on China’s forest biomass carbon sinks. Our results suggest that China forests can continue to act as a large carbon sinks in the near future because of the contributions of management of low- and medium-biomass forests, afforestation and nitrogen deposition. [ABSTRACT FROM AUTHOR]

Exosomes are vesicle-like bodies of that are actively secreted by cells to the extracellular surrounding with a diameter of 40–100 nm. They have several physiological functions, such as cell-cell communication, antitumor immunity, and angiogenesis promotion. Exosomes have many important roles and are extensively distributed in various fluids throughout the body, and therefore, they are of significant interest to researchers in diverse fields. Based on the characteristics and physiological functions of exosomes, this review summarizes the research progression regarding the role of exosomes in the field of orthopedics in recent years and highlights the association between exosomes and Chinese herbal medicines, to contribute to the application of exosomes in orthopedics and Chinese herbal medicines in the future. Moreover,the combined application of Chinese herbal medicines and exosomes can promote the modernization of Chinese herbal medicines. [ABSTRACT FROM AUTHOR]

Abstract: Several studies have reported different estimates for forest biomass carbon (C) stocks in China. The discrepancy among these estimates may be largely attributed to the methods used. In this study, we used three methods [mean biomass density method (MBM), mean ratio method (MRM), and continuous biomass expansion factor (BEF) method (abbreviated as CBM)] applied to forest inventory data to estimate China''s forest biomass C stocks and their changes from 1984 to 2003. The three methods generated various estimates of the biomass C stocks: the lowest (4.0–5.9PgC) from CBM and the highest (5.7–7.7PgC) from MBM, with an intermediate estimate (4.2–6.2PgC) from MRM. Forest age class is a major factor responsible for these method-induced differences. MBM overestimates biomass for young-aged forests, but underestimates biomass for old-aged forests; while the reverse is true for MRM. Further, the three methods resulted in different estimates of biomass C stocks for different forest types. For temperate/subtropical mixed forests, MBM generated a 92% higher estimate than CBM and MRM generated a 14% lower than CBM. The degree of the overestimates is closely related with the proportion of young-aged forest within total area of each forest type. [Copyright &y& Elsevier]

[Display omitted] • Clostridium was a major bacterium responsible for proteins and lipids degradation. • Highest biomethane at 2% SHW was due to high Methanosaeta (77.15%) abundance. • High VFAs and ammonia accumulation at 8% SHW caused permanent AD inhibition. • Acetoclastic methanogenesis shifted to hydrogenotrophic at high ammonia and VFAs. The slaughterhouse waste (SHW) contains high organics which makes SHW a feasible feedstock for anaerobic digestion (AD). The present study systematically assessed the microbiome response and biomethanation along with the production of volatile fatty acids (VFAs) and ammonia under 2%, 4%, 6%, and 8% (w v−1) loadings of SHW in AD. The optimum loading was 2% SHW which resulted in maximum biomethane production and VFAs consumption. A higher SHW concentration (4% and 6%) resulted in a prolonged lag-phase and decreased biomethane production. High VFAs (28.88 g L−1) and ammonia nitrogen (>4 g L−1) accumulation were observed at 8% SHW leading to permanent inhibition of biomethane and methanogenic archaea. An increase in ammonia and VFAs concentration, at 4% and 6% SHW loadings, shifted the methanogenic pathway from acetoclastic to hydrogenotrophic lead by Methanoculleus. Acetoclastic Methanosaeta (77.15%) dominated the reactors loaded with 2% SHW resulting in the highest biomethane production. [ABSTRACT FROM AUTHOR]

China is experiencing severe tropospheric ozone pollution, especially during the summer period in cities. Previous studies have assessed the role of meteorological conditions and anthropogenic precursors in shaping the diurnal variation of ozone concentration in some Chinese cities or the spatial patterns of daytime ozone concentration, but less is known about the spatial variation and main regulators of the diurnal cycle of summer ozone concentrations in Chinese cities. Using monitoring data from 367 cities, we analyzed the spatial patterns and main regulators of daytime maximum, nighttime minimum and diurnal difference of summer (June–August) ozone concentration during 2015–2019. National mean values and standard deviations of daytime maximum and nighttime minimum of summer surface ozone concentration were 124.1 ± 27.5 and 33.4 ± 13.0 μg m−3, resulting in a diurnal difference of 90.7 ± 25.2 μg m−3. High values of daytime maximum, nighttime minimum, and diurnal difference of summer ozone concentration occurred in cities in northern China, especially in the North China Plain, and several city agglomerations in southern China. Daytime maximum ozone concentration was higher in cities with higher daytime PM 2.5 and NO 2 concentrations, lower daytime precipitation and lower elevation. Nighttime minimum ozone concentration increased with lower nighttime precipitation, lower NO 2 concentration and CO concentration, higher nighttime maximum PM 2.5 concentration and higher elevation. Diurnal difference of ozone concentration increased with lower elevation, lower daytime precipitation, and higher diurnal difference of CO and NO 2 concentrations. Our findings highlight different regulators for daytime and nighttime ozone and imply the need of joint regulation of PM 2.5 and NO 2 emissions to control ozone pollution. [Display omitted] • The diurnal cycles of summer ozone concentration were analyzed across Chinese cities. • Daytime maximum ozone concentration was high and harmful while the nighttime minimum was relatively low and safe. • PM 2.5 , NO 2 , precipitation, and elevation explained 71% of the spatial variation in daytime maximum ozone concentration. • PM 2.5 , NO 2 , CO, precipitation, and elevation explained 48% of the spatial variation in nighttime minimum ozone concentration. • Elevation, CO, NO 2 , and precipitation explained 48% of the spatial variation in diurnal difference of ozone concentration. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is a biological process, encompasses the treatment and stabilization of complex organic matter to extract renewable biomethane fuel through microbial interaction in the digester. The main aim of the current study is to investigate the microbial community of anaerobic digestion sludge (ADS), collected at different periods from a mesophilic operating anaerobic digester. The core group of bacteria in ADS including Firmicutes, Bacteroidetes, and Proteobacteria represented more than 60% of the core bacterial community. In ADS (I), the supremacy of Cloacimonetes (18%) was also observed. In ADS (II), the dominance of Anaerobacter (8%) showed the effect of substrate composition on the microbial structure. However, 91% relative abundance of Firmicutes was observed in ADS (III). The hydrogenotrophic methanogens belonging to order Methanomicrobiales and Methanobacteriales exhibited dominance in all three ADSs (> 60%). No specific variations in the archaeal community might be attributed to the presence of beneficial bacterial species. This study provides all the detailed functional roles of microbes involved in AD which can further be used for additional environmental applications. [Display omitted] • ADS II showed the highest volatile solids (36.8 g/L) content for enhanced biomethanation. • The microbial communities showed a stable trend at the phylum level in all ADSs. • Firmicutes and Bacteroidetes essential for hydrolysis were >60% in all ADS. • Archaeal community was dominated by Methanomicrobiales and Methanobacteriales. [ABSTRACT FROM AUTHOR]

Mapping the global distribution of forest canopy height is important for estimating forest biomass and terrestrial carbon flux. In this study, we present a global map of mean forest canopy height at 500 m spatial resolution obtained by combining Geoscience Laser Altimeter System (GLAS) data acquired from 2005 to 2006 and 13 ancillary variables, including seven climatic variables and six remote sensing variables (nadir BRDF-adjusted reflectance at red and NIR bands, tree cover, anisotropic factor, accumulated Enhanced Vegetation Index, and elevation). The original contributions of this study include the following: (1) The wavelet method was applied to complement the GLA14 product to identify the ground peak and the top-canopy peak. We found that it was useful for dealing with waveforms with low reconstruction accuracy. (2) GLAS data from the leafless season were not used for non-evergreen forest because the height retrieval results exhibited underestimation and strong variations. (3) The anisotropic factor (ANIF), an indicator related to surface structure, was included as an ancillary variable for the first time and was determined to be important for height modeling in the Asian and North American regions. (4) The balanced random forest (BRF) algorithm was applied to register GLAS mean forest canopy height to a 500 m grid considering the small proportion of extreme height classes (tall and short trees), and it achieved good performance in terms of modeling accuracy (RMSE = 2.75 to 4.45 m) and preserving data variation. An inter-comparison among three global forest height maps [the present study, Lefsky (2010) , and Simard et al. (2011) ] was implemented in a pixel-by-pixel manner. High agreement (R 2 = 0.73, RMSE = 4.49 m) was determined between the present study and Simard et al., whereas the result from Lefsky was notably different from the other two results (R 2 = 0.14, RMSE = 8.92 m, compared with the present study; R 2 = 0.11, RMSE = 11.19 m, compared with Simard et al.). Large disparities were generally associated with evergreen broadleaf forests in South America, deciduous needleleaf forests in Europe and Russian North Asia, and evergreen needleleaf forests on the West Coast of North America. Differences in the height metric were a main factor affecting the disparities among the three results. Validation against field survey data acquired from the Distributed Active Archive Center indicated the accuracy of our mean forest canopy height map (R 2 = 0.63, RMSE = 4.68 m, n = 59). [ABSTRACT FROM AUTHOR]