Sci Total Environ
November 2024
Global estimates of the size, distribution, and vulnerability of soil inorganic carbon (SIC) remain largely unquantified. By compiling 223,593 field-based measurements and developing machine-learning models, we report that global soils store 2305 ± 636 (±1 SD) billion tonnes of carbon as SIC over the top 2-meter depth. Under future scenarios, soil acidification associated with nitrogen additions to terrestrial ecosystems will reduce global SIC (0.
View Article and Find Full Text PDFFuture phosphorus (P) shortages could seriously affect terrestrial productivity and food security. We investigated the changes in topsoil available P (AP) and total P (TP) in China's forests, grasslands, paddy fields, and upland croplands during the 1980s-2010s based on substantial repeated soil P measurements (63,220 samples in the 1980s, 2000s, and 2010s) and machine learning techniques. Between the 1980s and 2010s, total soil AP stock increased with a small but significant rate of 0.
View Article and Find Full Text PDFBackground: We assess the effects of standard decompressive craniectomy with stepwise decompression of the intracranial compartment on the postoperative neurologic function, hemodynamics, and Glasgow Outcome Scale (GOS) score of patients with severe traumatic brain injury (sTBI).
Methods: One hundred sTBI patients admitted from July 2017 to February 2019 were enrolled and randomly divided into step and standard groups ( = 50) using a random number table. The standard group received traditional standard decompression during surgery, while the step group underwent multistep decompression during surgery.
Soil spatial information has traditionally been presented as polygon maps at coarse scales. Solving global and local issues, including food security, water regulation, land degradation, and climate change requires higher quality, more consistent and detailed soil information. Accurate prediction of soil variation over large and complex areas with limited samples remains a challenge, which is especially significant for China due to its vast land area which contains the most diverse soil landscapes in the world.
View Article and Find Full Text PDFAccumulation of soluble organic nitrogen (SON) in soil poses a significant threat to groundwater quality and plays an important role in regulating the global nitrogen cycle; however, most related studies have focused only on the upper 100-cm soil layers. Surface land-use management and soil properties may affect the vertical distribution of SON; however, their influence is poorly understood in deep soil layers. Therefore, this study assessed the response of SON concentration, pattern, and storage in deep regoliths to land-use conversion from woodlands to orchards in a subtropical hilly region.
View Article and Find Full Text PDFSoil microbial biogeographical patterns have been widely explored from horizontal to vertical scales. However, studies of microbial vertical distributions were still limited (e.g.
View Article and Find Full Text PDFViruses are extremely abundant in the soil environment and have potential roles in impacting on microbial population, evolution, and nutrient biogeochemical cycles. However, how environment and climate changes affect soil viruses is still poorly understood. Here, a metagenomic approach was used to investigate the distribution, diversity, and potential biogeochemical impacts of DNA viruses in 12 grassland soils under three precipitation gradients on the Qinghai-Tibet Plateau, which is one of the most sensitive areas to climate change.
View Article and Find Full Text PDFWidespread soil acidification due to atmospheric acid deposition and agricultural fertilization may greatly accelerate soil carbonate dissolution and CO release. However, to date, few studies have addressed these processes. Here, we use meta-analysis and nationwide-survey datasets to investigate changes in soil inorganic carbon (SIC) stocks in China.
View Article and Find Full Text PDFNeuropsychiatr Dis Treat
January 2022
Objective: Complement C1q is implicated in neuroinflammation. We intended to discern the relationship between serum C1q levels and severity in addition to prognosis following traumatic brain injury (TBI).
Methods: In this prospective, observational study, serum C1q levels were quantified in 188 TBI patients and 188 healthy controls.
Purpose: Subarachnoid hemorrhage (SAH) is a common complication of cerebral vascular disease. Hydrogen has been reported to alleviate early brain injury (EBI) through oxidative stress injury, reactive oxygen species (ROS), and autophagy. Autophagy is a programmed cell death mechanism that plays a vital role in neuronal cell death after SAH.
View Article and Find Full Text PDFNitrate accumulated deep (>100 cm) in the regolith (soil and saprolite) threatens groundwater quality, but most studies focus only on nitrate nearer the surface (<100 cm). Surface soil management versus regolith interactions affect deep nitrate leaching, but their combined impact remains unclear. This study measured how deep nitrate accumulation was affected by crop practices including orchard/cropland planting years, regolith structure, and soil properties in highly weathered subtropical red soils.
View Article and Find Full Text PDFStudy Design: Bibliometric analysis.
Objective: This study aims to identify and summarize the articles related to sacral fracture surgery, to compare the papers from different countries and journals, to show the trends of researches on sacral fracture surgery.
Summary Of Background Data: In recent years, studies on sacral fracture are growing rapidly, but there were no bibliometric studies regarding sacral fracture surgery.
Subsurface soil bacterial community composition and the controlling factors remain largely unknown, especially the micro-zone differentiation of community composition within a horizon. We studied a plinthic horizon to determine how different micro-zones in a horizon affect the bacterial community. The plinthic horizon is a net-like horizon characterized by the segregation of iron forms as shown by contrasting red matrix and white veins, which share common macro-environmental conditions such as climate and land use but differ only in physical and chemical compositions.
View Article and Find Full Text PDFBacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
November 2012
The Excitation-emission matrix (EEM) fluorescence spectra of dissolved organic matter (DOM) are not only dependent on the chemical structure of DOM as well as the local chemical environment around the DOM, but also dependent on the instrument employed for the analysis. Thus, in order to get the real spectra of the DOM, spectra correction of the effect of the instrument-specific response is necessary. However, some studies corrected DOM spectra, while still some studies didn't, leading to inconformity when comparing the data and the results from different groups.
View Article and Find Full Text PDFThe photocatalytic degradation of pentachlorophenol (PCP) using a TiO(2) catalyst in a surfactant-containing system was investigated. PCP abatement by photocatalysis was significantly enhanced by the addition of cationic and nonionic surfactants, both single and mixed, at appropriate concentrations. The enhanced photodegradation can be mainly attributed to the formation of admicelles on the TiO(2) surface.
View Article and Find Full Text PDFA flow reaction system was utilized to investigate lignocellulose conversion using combined supercritical/subcritical conditions for hexose production. Initially, investigation of cellulose hydrolysis in supercritical water and optimization of reaction parameters were done. Oligosaccharide yields reached over 30% at cellulose concentrations of 3-5 gL(-1) and reaction times of 6-10s at 375 °C, and 2.
View Article and Find Full Text PDFPancreatic cancer is a highly aggressive malignant disease. Gemcitabine is currently the standard first-line chemotherapeutic agent for pancreatic cancer. As members of apoptosis inhibitors, Survivin and XIAP play an important role in chemotherapy resistance in pancreatic cancer.
View Article and Find Full Text PDFFluorescence Excitation-Emission Matrix (EEM) combined with fluorescence regional integration (FRI) and parallel factor analysis (PARAFAC) was employed to tracing the properties and behavior of the water-execrable organic matter (WEOM) from landfilled municipal solid waste (MSW) for assessing the biological stability. The 3-components PARAFAC model developed showed the WEOM dominated by two humic-like materials (components C1 and C2) which were highly correlated and behave similarly in this work, and a protein-like material (component C3). The percent fluorescence response P(i,n) from FRI and maximum fluorescence intensity F(max) of the components from PARAFAC proved to be sensitive indicators of the bulk properties and transformation of WEOM during landfill stabilization.
View Article and Find Full Text PDFThe successful design and operation of in situ treatment systems using air and water additions for sustainable landfilling are constrained by a lack of knowledge of the key parameters, such as field air permeability and hydraulic conductivity of landfilled municipal solid waste (MSW). This work provides data on the field air permeability k(a) and hydraulic conductivity K(w) of MSW obtained by conducting short-term air and water injection tests at a landfill in Beijing, China. The k(a) and K(w) values are found to in the range of 1.
View Article and Find Full Text PDFSuccessful modeling of liquid and air flow and hence designing of liquid and air addition systems in the landfills are constrained by the lack of key parameters of unsaturated hydraulic properties of municipal solid waste (MSW), which are strongly dependent on the depth of burial and the degree of decomposition. In this study, water retention curves (WRC) of MSW are measured using pressure plate method on samples repacked according to the in situ unit weight measured during borehole sampling, representing the MSW in shallow, middle, and deep layers. The measured WRC of MSW is well-reproduced by the van Genuchten-Mualem model, and is used to predict the unsaturated hydraulic properties of MSW, including water retention characteristics and unsaturated hydraulic conductivity.
View Article and Find Full Text PDFJ Environ Sci (China)
June 2013
The adsorption of cationic-nonionic mixed surfactant onto bentonite and its effect on bentonite structure were investigated. The objective was to improve the understanding of surfactant behavior on clay mineral for its possible use in remediation technologies of soil and groundwater contaminated by toxic organic compounds. The cationic surfactant used was hexadecylpyridinium bromide (HDPB), and the nonionic surfactant was Triton X-100 (TX100).
View Article and Find Full Text PDFThis study seeks to assess the biological stability of landfilled municipal solid waste (MSW) based on the changes in organic matter, as revealed by thermogravimetric analysis and Fourier transform infrared (FTIR) spectroscopy. Derivate thermogravimetry profiles (DTG) showed a reduction in peak intensity at 200-350 °C (DTG2), while an increase in peak intensity and a shift towards higher temperature at 400-600 °C (DTG3). The decrease in the peak intensity of the aliphatic methylene at 2920 and 2850 cm(-1), and the increase of aromatic substances and polysaccharide at 1640 cm(-1) in the FTIR spectra also confirm the changes.
View Article and Find Full Text PDF