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Synergistic catalytic AB hydrolysis to generate hydrogen was achieved over AgCo@CN synthesized by auto-reduction between Co@CN and a Ag precursor.

Background Intracerebral hemorrhage (ICH) is aggravated by immune cells that participate in the inflammatory response from the blood-brain barrier (BBB). O-Glycosylation has been reported to regulate the inflammatory response in the central nervous system but its cerebral protective effects remain unknown. Therefore, this study was carried out to investigate the protective effects of O-GlcNAcylation in a murine model of ICH and the possible mechanisms involved. Methods The effects of O-GlcNAcylation on hematoma and edema formation were tested using pathological and dry/wet weight methods, whereas its effects on neural function were determined using neurologic tests. The effect of O-GlcNAcylation on BBB integrity was determined by Evans blue dye extrusion. Flow cytometry was used to quantify the immune cells in the central nervous system. Immunofluorescence was used to detect the protective effect of O-GlcNAcylation in ICH. Results The hematoma volume was significantly lower in the prevention and treatment groups than in the control group after ICH induction, indicating that O-GlcNAcylation had reduced the formation of cerebral hematoma in ICH. In the prevention and treatment groups, the modified neurological severity score, corner turn test and rotating rod test results were improved and the BBB integrity was better than that in the control group. O-GlcNAcylation also regulated the microglia, neutrophils and other central nervous system immune cells after ICH, effectively reducing the inflammatory response. Conclusions O-GlcNAcylation played an important role in suppressing the inflammatory response, enhancing the BBB integrity and reducing edema after ICH.

Developing high-efficiency and low-cost catalysts for hydrogen evolution from hydrolysis of ammonia borane (AB) is significant and critical for the exploitation and utilization of hydrogen energy. Herein, the in-situ fabrication of well-dispersed and small bimetallic RuNi alloy nanoparticles (NPs) with tuned compositions and concomitant hydrolysis of AB are successfully achieved by using graphitic carbon nitride (g-C3N4) as a NP support without additional stabilizing ligands. The optimized Ru1Ni7.5/g-C3N4 catalyst exhibits an excellent catalytic activity with a high turnover frequency of 901 min−1 and an activation energy of 28.46 kJ mol−1 without any base additives, overtaking the activities of many previously reported catalysts for AB hydrolysis. The kinetic studies indicate that the AB hydrolysis over Ru1Ni7.5/g-C3N4 is first-order and zero-order reactions with respect to the catalyst and AB concentrations, respectively. Ru1Ni7.5/g-C3N4 has a good recyclability with 46% of the initial catalytic activity retained even after five runs. The high performance of Ru1Ni7.5/g-C3N4 should be assigned to the small-sized alloy NPs with abundant accessible active sites and the synergistic effect between the composition-tuned Ru–Ni bimetals. This work highlights a potentially powerful and simple strategy for preparing highly active bimetallic alloy catalysts for AB hydrolysis to generate hydrogen.

Ru-based bimetallic alloy nanoparticles (NPs) have been demonstrated as efficiently catalytic sites for hydrogen evolution from ammonia borane (AB) hydrolysis, but their facile syntheses with ultrafine sizes and superior activity are still challengeable. Herein, we report the in situ fabrication of ultrafine RuCo alloy NPs and concomitant AB hydrolysis using graphite carbon nitride (g-C3N4) as a supporting matrix. Notably, the catalytic activity of Ru1Co1−x/g-C3N4 is mostly dependent on the composition of Ru and Co metals and an optimal synergistic catalysis for AB hydrolysis is achieved using Ru0.1Co0.9/g-C3N4 as a catalyst. An extraordinary turnover frequency of 1260 min−1 is obtained at 25 °C without the use of any basic additives, which surpasses most of the noble metal heterogeneous catalysts. The efficient catalytic activity of Ru0.1Co0.9/g-C3N4 is attributed to the synergistic alloying effect between Ru and Co NPs, and the abundant nitrogen-containing functional groups on g-C3N4 serve as the anchoring sites for ultrafine and uniformly distributed RuCo alloy NPs. The high catalytic activity endows Ru0.1Co0.9/g-C3N4 with desirable potential in hydrogen generation from the hydrolysis of chemical storage materials.

Effects of two typical comminution methods (shearing and blending) on structural and biochemical properties of silver carp surimi were comparatively investigated. Surimi myofibrils in striated appearance were progressively disrupted within 15 min of blending. The myofibrils were completely disintegrated after shearing for 5 min. Surface hydrophobicity of surimi increased and then gradually decreased (p 0.05) under shearing, while it continuously increased (p 0.05) under blending. As shearing time was extended, α-helical structure decreased and β-sheet structure increased simultaneously; surface active sulfhydryl content (SH) increased and then decreased (p 0.05); and intensity of myosin heavy chain (MHC) was gradually reduced. However, secondary structure, MHC intensity and SH were slightly changed as blending time extended. Ca

The solubilities of d-tryptophan in neat n-propanol, ethyl acetate, ethylene glycol (EG), n-butanol, acetonitrile, 1-octanol, and dimethyl sulfoxide and of l-tyrosine in ethyl acetate, EG, isopropa...

Background Blending and shearing, two types of comminution methods, are widely used in the manufacturing of surimi-based products. The comminution methods applied are varied to product types and manufacturers. In this study effects of different comminution methods (blending and shearing) on gelling properties of silver carp surimi were investigated. Results Regardless of comminution methods, breaking force, penetration distance and water holding capacity of surimi gel significantly increased with comminution duration up to 10 min. As compared with blending, those values under shearing of the same duration were significantly higher. Within 3 min of comminuting whiteness values of gels by shearing were significantly higher than those by blending. Electrophoresis studies showed that comminution method had no obvious effect on protein patterns. Scanning electron microscopy images revealed that more uniform and denser network was formed in the surimi gels made by shearing. Water distribution of the gels made by shearing was obviously more uniform according to magnetic resonance imaging analysis. Conclusion Our results suggested that with respect to blending, shearing was a better choice to maximize the gelling ability of silver carp surimi, which resulted in the higher values of texture, whiteness and water holding capacity. It could be attributed to the denser three-dimensional network and more uniform water distribution of the surimi gel prepared by shearing. © 2019 Society of Chemical Industry.

The equilibrium solubilities of chlorhexidine in four solvent mixtures of methanol (1) + water (2), ethanol (1) + water (2), DMF (1) + water (2) and 1,4-dioxane (1) + w water (2) at temperature range from (278.15 to 318.15) K were reported. At the same composition of methanol, ethanol, DMF or 1,4-dioxane and temperature, the mole fraction solubility of chlorhexidine was highest in DMF (1) + w water (2) mixtures, and lowest in ethanol (1) + w water (2) mixtures. By using the Jouyban-Acree model, van’t Hoff-Jouyban-Acree model and Apelblat-Jouyban-Acree model, chlorhexidine solubility was well correlated obtaining RAD lower than 1.69% and RMSD lower than 0.87 × 10−4. The dissolution process of chlorhexidine in solvent solutions was endothermic for the dissolution process. To study the solvent effect, solubility data were correlated to KAT parameters and cavity term on the basis of linear solvation energy relationships concept. Results indicate the key effect of cavity term and π∗ in aqueous methanol and ethanol mixtures; cavity term in aqueous DMF mixtures; and cavity term, β and π∗ in aqueous 1,4-dioxan mixtures. Quantitative values for the local mole fraction of methanol (ethanol, DMF or 1,4-dioxane) and water around the chlorhexidine were computed by using the IKBI method applied to the determined solubility data. Chlorhexidine was preferentially solvated by water for the four solvent mixtures in water-rich compositions; while in intermediate and co-solvent-rich composition for ethanol (DMF, 1,4-dioxane) (1) + w water (2) mixtures, chlorhexidine is preferentially solvated by the co-solvent. The preferential solvation magnitude of chlorhexidine was highest in 1,4-dioxane mixtures than in the other three solvent mixtures.

Background: It is important to predict poststroke cognitive outcome to guide individualized treatment and prevention strategy. We aimed to evaluate the predictive value of the combination of a serum biomarker for axonal damage (neurofilament light chain [NfL]) and neuroimaging markers (volume of infarction and white matter hyperintensities [WMH]) for neuronal abnormality in poststroke cognitive outcome. Methods: A total of 1028 patients were screened; among them, 144 patients with acute ischemic stroke (stroke group) and 30 patients without stroke (control group) were enrolled. Serum NfL levels of samples obtained from both groups were measured through single molecule array assay. Neuroimaging markers of neuroaxonal injury, including infarct volume and WMH in the stroke group were quantified on magnetic resonance images using an in-house MATLAB code (MATLAB 2017; MathWorks). The primary outcome was the functional independence measure (FIM) cognitive subscores on discharge. We assessed the association of serum NfL levels and neuroimaging markers with cognitive outcome. The prognosis value of the combination of serum NfL levels and imaging markers for predicting FIM cognitive subscores on discharge was calculated using the area under curve (AUC) of the receiver operating characteristic. Results: Serum NfL levels of the stroke group were 9-fold higher than those of the control group (1449.7 vs 157.2 pg/mL, n = 144/30, P < .001). There was a correlation of serum NfL levels with infarct volume ( r = 0.530, P < .001) and functional outcome, including FIM cognitive subscores ( r = −0.387, P < .001) and FIM motor subscores on admission ( r = −0.306, P < .001), but not with WMH volume after adjusting for infarct volume ( r = −0.196, P = .245). Serum NfL levels on admission independently predicted poststroke FIM cognitive subscores on discharge (AUC = 0.672, P < .001). The predictive value for poststroke cognitive outcome was improved by combining serum NfL levels with infarct and WMH volume (AUC = 0.760, P < .001). Conclusion: The combination of serum NfL levels with volume of infarct and WMH shows an improved predictive value for cognitive function during acute rehabilitation phase after stroke, providing a promising panel of biomarkers for prognosis and guidance of treatment.

Supplemental material, sj-docx-1-nnr-10.1177_1545968321989354 for Combination of Serum Neurofilament Light Chain Levels and MRI Markers to Predict Cognitive Function in Ischemic Stroke by Yuan Peng, Qianfeng Li, Lei Qin, Yating He, Xun Luo, Yue Lan, Xin Chen, Xin Wang and Qing Mei Wang in Neurorehabilitation and Neural Repair

Heteroatom-doped porous carbons that possess large surface areas and well-defined porosity show great promise in heterogeneous catalysis, whereas their syntheses inevitably require complicated steps, hazardous activation and functional reagents, and an inert gas atmosphere. Herein, a one-pot synthetic strategy to oxygen-rich porous nitrogen-doped carbon (OPNC) is developed through pyrolysis of ethylenediamine tetra-acetic acid tetra-sodium in air without any activation and functionalization agents. The as-prepared OPNC with more surface oxygenated groups and mesopores not only benefits synthesis of well-dispersed ultrafine Rh nanoparticles (NPs) with abundant accessible active sites, but also facilitates the diffusion of reactants and avoids mass transfer limitations, thereby considerably contributes to a high performance toward AB hydrolysis. Specifically, the optimal Rh/OPNC exhibits a high activity toward AB hydrolysis with a turnover frequency (TOF) of 433 min−1. The kinetic isotope studies indicate that the cleavage of O H bond in H2O molecules is the rate-determining step (RDS). The Rh/OPNC can be reused for five repetitive cycles with approximately 62% remained activity of the first cycle. The catalytic activity of Rh/OPNC can be further improved with a very high TOF of 1201 min−1 in alkaline solution. This study proposes a simple and sustainable pathway to synthesize efficient catalyst support for depositing metal NPs toward AB hydrolysis.

The first listing of hog futures provides farmers with new means of risk prevention, value preservation and income increase, but the factors affecting their willingness to participate in hog futures are worthy of in-depth analysis. Based on survey data in Sichuan Province, this paper uses the oprobit model to analyze the factors affecting farmers’ willingness to participate in hog futures. We finally find that education level, breeding cooperation, price stability, information channels, risk aversion, and futures training can significantly improve farmers’ willingness to participate in hog futures. On the contrary, income will significantly reduce farmers’ willingness to participate in hog futures. To the end, this paper puts forward relevant suggestions to help promote the implementation of hog futures.

Background Altered calcium homeostasis is hypothesized to underlie Alzheimer's disease (AD). However, it remains unclear whether serum calcium levels are genetically associated with AD risk. Objective To develop effective therapies, we should establish the causal link between serum calcium levels and AD. Methods Here, we performed a Mendelian randomization study to investigate the causal association of increased serum calcium levels with AD risk using the genetic variants from a large-scale serum calcium genome-wide association study (GWAS) dataset (61,079 individuals of European descent) and a large-scale AD GWAS dataset (54,162 individuals including 17,008 AD cases and 37,154 controls of European descent). Here, we selected the inverse-variance weighted (IVW) as the main analysis method. Meanwhile, we selected other three sensitivity analysis methods to examine the robustness of the IVW estimate. Results IVW analysis showed that the increased serum calcium level (per 1 standard deviation (SD) increase 0.5 mg/dL) was significantly associated with a reduced AD risk (OR = 0.57, 95% CI 0.35-0.95, p = 0.031). Meanwhile, all the estimates from other sensitivity analysis methods were consistent with the IVW estimate in terms of direction and magnitude. Conclusion In summary, we provided evidence that increased serum calcium levels could reduce the risk of AD. Meanwhile, randomized controlled study should be conducted to clarify whether diet calcium intake or calcium supplement, or both could reduce the risk of AD.

Studies have suggested that heightened neuroinflammation contributes to the pathogenesis of depressive disorder. A major participant in neuroinflammation is microglia, and fractalkine signaling (which comprises the chemokine CX3CL1, mainly expressed by neurons, and its receptor CX3CR1, almost exclusively present on microglia in healthy brains) has been reported to critically regulate microglial activity. The aim of this study was to investigate whether CX3CR1 deficiency was associated with a different outcome following chronic unpredictable stress (CUS) and the possible mechanism. Wild-type (WT) and CX3CR1-deficient (CX3CR1-/-) mice were subjected to CUS for 3 weeks. CX3CR1-/- mice displayed a better performance through sucrose preference test, open field test and forced swim test, which demonstrated that CX3CR1 deficiency alleviated depressive-like disturbances, such as anhedonia, anxiety or hopelessness. Nevertheless, CX3CR1-/- mice also showed less severe cognitive impairment from the results of Morris Water Maze and Novel object recognition. Long-term potentiation was recorded to test the synaptic plasticity and its result was consistent with that of cognitive ability tests. Both results of real time-PCR and immunofluorescence staining demonstrated that CX3CR1 deficiency facilitated the alternative activation of microglia, thus attenuated the release of inflammatory cytokines, which was verified by ELISA and flow cytometry. Maybe due to the mitigated neuroinflammation, CX3CR1-deficient mice showed higher resilience to CUS-induced blood brain barrier hyperpermeability and loss of dendrite spine (as showed by Golgi and DiI staining) than WT group. All of above results indicated that hampering neuron-microglia communication via CX3CR1-CX3CL1 pathway attenuated the effects of CUS on depressive-like disturbances and cognitive impairment.

Functional carbons that can provide abundant anchoring sites for metal nanoparticles (NPs) have shown great promise in boosting the catalytic activity for hydrolysis of ammonia borane (AB), while the synthetic recipes for some of them are complicated, time-consuming and hazardous together with a low yield. Herein, we develop a facile and easily scalable one-pot synthetic strategy to nitrogen-doped carbon skeleton (NCS) via direct pyrolysis of ethylenediamine tetra-acetic acid tetra-sodium salt in air. Attributing to the anchoring sites from abundant nitrogen-dopant and nanoporous structure of NCS, ultrasmall RuNi alloy NPs are highly distributed on NCS. The as-prepared RuNi/NCS can be used as a highly active catalyst for hydrogen production from AB hydrolysis at room temperature. Specifically, the optimal Ru1Ni1.90/NCS delivers an excellent catalytic activity with a very high turnover frequency of 1017 min−1 in basic solution, superior to many previous results. The kinetic studies indicate that AB hydrolysis catalyzed by Ru1Ni1.90/NCS is first-order and zero-order in terms of Ru and AB concentrations, respectively. Additionally, the isotopic analysis reveals that the O–H bond cleavage of water is the rate-determining step. The high catalytic activity of Ru1Ni1.90/NCS can be assigned to the ultrasmall RuNi nanostructure, highly nanoporous carbon matrix, and abundant N-dopant and the synergistic catalysis between the two metals. This study offers a simple synthetic protocol for construction of metal-carbon hybrid toward hydrogen generation from the hydrolysis of chemical storage materials.

O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) is involved in the regulation of many cellular cascades and neurological diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. In the brain, the expression of O-GlcNAcylation is notably heightened, as is that of O-linked N-acetylglucosaminyltransferase (OGT) and β-N-acetylglucosaminidase (OGA), the presence of which is prominent in many regions of neurological importance. Most importantly, O-GlcNAcylation is believed to contribute to the normal functioning of neurons; conversely, its dysregulation participates in the pathogenesis of neurological disorders. In neurodegenerative diseases, O-GlcNAcylation of the brain's key proteins, such as tau and amyloid-β, interacts with their phosphorylation, thereby triggering the formation of neurofibrillary tangles and amyloid plaques. An increase of O-GlcNAcylation by pharmacological intervention prevents neuronal loss. Additionally, O-GlcNAcylation is stress sensitive, and its elevation is cytoprotective. Increased O-GlcNAcylation ameliorated brain damage in victims of both trauma-hemorrhage and stroke. In this review, we summarize the current understanding of O-GlcNAcylation's physiological and pathological roles in the nervous system and provide a foundation for development of a therapeutic strategy for neurological disorders.

Experimental autoimmune neuritis (EAN) is a CD4+ T-cell-mediated autoimmune inflammatory demyelinating disease of the peripheral nervous system. It has been replicated in an animal model of human inflammatory demyelinating polyradiculoneuropathy, Guillain-Barre syndrome. In this study, we evaluated the therapeutic efficacy of a selective inhibitor of the immunoproteasome subunit, low-MW polypeptide 7 (PR-957) in rats with EAN. Our results showed that PR-957 significantly delayed onset day, reduced severity and shortened duration of EAN, and alleviated demyelination and inflammatory infiltration in sciatic nerves. In addition to significantly regulating expression of the cytokine profile, PR-957 treatment down-regulated the proportion of proinflammatory T-helper (Th)17 cells in sciatic nerves and spleens of rats with EAN. Data presented show the role of PR-957 in the signal transducer and activator of transcription 3 (STAT3) pathway. PR-957 not only decreased expression of IL-6 and IL-23 but also led to down-regulation of STAT3 phosphorylation in CD4+ T cells. Regulation of the STAT3 pathway led to a reduction in retinoid-related orphan nuclear receptor γ t and IL-17 production. Furthermore, reduction of STAT3 phosphorylation may have directly suppressed Th17-cell differentiation. Therefore, our study demonstrates that PR-957 could potently alleviate inflammation in rats with EAN and that it may be a likely candidate for treating Guillain-Barre syndrome.-Liu, H., Wan, C., Ding, Y., Han, R., He, Y., Xiao, J., Hao, J. PR-957, a selective inhibitor of immunoproteasome subunit low-MW polypeptide 7, attenuates experimental autoimmune neuritis by suppressing Th17-cell differentiation and regulating cytokine production.

The equilibrium 5-nitrosalicylaldehyde solubility in methanol (1) + water (2), ethanol (1) + water (2), isopropanol (1) + water (2) and acetonitrile (1) + water (2) mixtures was determined by a shake-flask method from 273.15 K to 313.15 K under local pressure of 101.2 kPa. At the same mass fraction of methanol (ethanol, isopropanol or acetonitrile) and temperature, the mole fraction solubility of 5-nitrosalicylaldehyde was greater in (acetonitrile + water) mixture than in ethanol (1) + water (2), isopropanol (1) + water (2) and methanol (1) + water (2) mixtures. The relative importance of solute–solvent and solvent–solvent interactions upon the solubility variation was valued by using the linear solvation energy relationship analysis of solvent effect. The method of inverse Kirkwood–Buff integrals was used to study the preferential solvation on the basis of thermodynamic solution properties. The preferential solvation parameters for methanol, ethanol, isopropanol and acetonitrile were positive in the four mixtures in co-solvent-rich and intermediate composition, indicating that 5-nitrosalicylaldehyde was solvated preferentially by the co-solvent. It is conjecturable that in these regions 5-nitrosalicylaldehyde acts as a Lewis acid with the alcohols’ molecules; while for the acetonitrile + water mixture, the preferential solvation could be attributed to polarization effects. Moreover, the drugs’ solubility was mathematically represented via the Jouyban-Acree model acquiring the average relative deviations

Estimating age through a single facial image is a classic and challenging topic in computer vision. Since facial images of the same age vary considerably, while those from different ages may look very similar. To address these problems, we propose an end-to-end deep embedding neural network for robust age estimation. Specifically, we jointly use classification loss and triplet-based ranking loss to train a deep embedding network, which maps the input facial images into an embedding metric space where features of the same age are compact and those from different ages are pushed away. Thus the deep embedding network can learn more discriminative features and improves the performance for age estimation. Additionally, to accelerate the convergence of the network, we adopt an online hard negative mining strategy during the triplet loss computation. Experimental results on public datasets MORPH II and FG-NET show the superiority of our approach compared to the state-of-the-art.

The Chinese steppe is undergoing a drastic increase in nitrogen (N) deposition, and the precipitation in this region is predicted to increase. However, the response of soil N2O emissions to the coupling changes of precipitation and N deposition in grassland ecosystem has been seldom discussed. A manipulative field experiment was conducted to investigate the individual and interactive effects of precipitation increase and N deposition on soil N2O efflux in semi-arid temperate grassland in Inner Mongolia during the growing seasons of 2010 and 2011.The treatments included four N addition levels [20 g N m(-2) y(-1) (N20) 10 gN m(-2) y(-1) (N10), 5 g N m(-2) y(-1) (N5), and a zero-N control (CK)] and two water application levels [natural precipitation for dry (D) and 15% increase of long-term mean annual precipitation for wet (W) treatments]. Results indicated that N and water addition both significantly increased soil N2O effluxes < 0.01). The maximum N2O emissions were observed within 2-3 days after N addition to all treatments, and the N2O effluxes in W treatments were generally higher than in D treatments for the same N input level. For the treatments without N inputs, the N2O emission peak of WCK was 9.8% higher than DCK in 2010. The effect of water addition on N2O emission was more evident when more N fertilizer was applied. For the high N input treatments, the maximum N2O emission of WN20 treatment was 222.6% higher than DN20 in 2010. The changes in N and water availabilities accounted for 91.3% (2010) and 75.6% (2011) of the N2O cumulative efflux variation among different treatments (P < 0.01). The N2O effluxes were significantly affected by the interactive effect between N and water in 2010 and 2011 (P < 0.05). Significant interannual variability in the cumulative N2O emissions was observed, the cumulative N2O emissions in 2011 were significantly lower than those in 2010 even though the summer of 2011 experienced higher rainfall (P < 0.01). Temperature also significantly influenced soil N2O emission apart from the effects of water and N. The temperature change accounted for 41.3% (W) to 47.2% (D) of the temporal variations in N2O emission during the relatively dry 2010. The combined changes in soil moisture, NH4+-N, and temperature accounted for 43.1% (D) to 54.5% (W) of the temporal variations in N2O emission in the relatively wet year of 2011. (C) 2015 Elsevier B.V. All rights reserved.

Background Post-traumatic Guillain-Barré syndrome (GBS) is a rarely described potentially life-threatening cause of weakness. We sought to elucidate the clinical features and electrophysiological patterns of post-traumatic GBS as an aid to diagnosis. Methods We retrospectively studied six patients diagnosed with post-traumatic GBS between 2014 and 2016 at Tianjin Medical University General Hospital, China. Clinical features, serum analysis, lumbar puncture results, electrophysiological examinations, and prognosis were assessed. Results All six patients had different degrees of muscular atrophy at nadir and in two, respiratory muscles were involved. Five also had damaged cranial nerves and four of these had serum antibodies against gangliosides. The most common electrophysiological findings were relatively normal distal latency, prominent reduction of compound muscle action potential amplitude, and absence of F-waves, which are consistent with an axonal form of GBS. Conclusions It is often overlooked that GBS can be triggered by non-infectious factors such as trauma and its short-term prognosis is poor. Therefore, it is important to analyze the clinical and electrophysiological features of GBS after trauma. Here we have shown that electrophysiological evaluations are helpful for diagnosing post-traumatic GBS. Early diagnosis may support appropriate treatment to help prevent morbidity and improve prognosis.

Grazing and cultivation are two important management practices worldwide that can cause significant soil organic carbon (SOC) losses. However, it remains elusive how soil microbes have responded to soil carbon changes under these two practices. Based on a four-decade long field experiment, this study investigated the effects of grazing and cultivation on SOC stocks and microbial properties in the semi-arid grasslands of China. We hypothesize that grazing and cultivation would deplete SOC and depress microbial activities under both practices. However, our hypotheses were only partially supported. As compared with the adjacent indigenous grasslands, SOC and microbial biomass carbon (MBC) were decreased by 20% or more under grazing and cultivation, which is consistent with the reduction of fungi abundance by 40% and 71%, respectively. The abundance of bacteria and actinomycetes was decreased under grazing but increased under cultivation, which likely enhanced microbial diversity in cultivation. Invertase activity decreased under the two treatments, while urease activity increased under grazing. These results suggest that nitrogen fertilizer input during cultivation may preferentially favor bacterial growth, in spite of SOC loss, due to rapid decomposition, while overgrazing may deteriorate the nitrogen supply to belowground microbes, thus stimulating the microbial production of nitrogen acquisition enzymes. This decade-long study demonstrated differential soil microbial responses under grazing and cultivation and has important applications for better management practices in the grassland ecosystem.

The estimation of forest biomass from synthetic aperture radar (SAR) data is limited by the lack of forest structure information. Interferometric synthetic aperture radar (InSAR) provides a means for the extraction of forest structure. The crucial issue in InSAR application is to parameterize forest structure and to link the parameter with InSAR observations. Model-based analysis enables exploring the theoretical linkages between InSAR observations and forest structure free from temporal decorrelation effects. In this paper, a semicoherent model (SCSR) was first developed and verified. A series of simulations at L-band was then made for both homogeneous and heterogeneous forests generated from a forest growth model. The forest structure was parameterized by four height indices. Aside from the height of scattering phase center (HSPC), the depth of scattering phase center (DSPC) was also proposed to characterize the scattering phase center of InSAR. The results showed that the behavior of homogeneous forest on InSAR data was quite different from that of heterogeneous forest. Special care was needed when the retrieval algorithms of forest biomass developed on a homogeneous forest were applied to a heterogeneous forest. Crown size-weighted height (CWH) and Lorey's height were correlated with the HSPC at all polarizations and with the DSPC at copolarization in both cases of homogeneous and heterogeneous forests. These findings indicated that CWH could be an alternative biomass indicator of the Lorey's height for biomass estimation, which can be derived from the combination of InSAR data and the elevation of the forest canopy top from lidar or high-resolution stereo images.

Litter decomposition is the fundamental process in nutrient cycling and soil carbon (C) sequestration in terrestrial ecosystems. The global-wide increase in nitrogen (N) inputs is expected to alter litter decomposition and, ultimately, affect ecosystem C storage and nutrient status. Temperate grassland ecosystems in China are usually N-deficient and particularly sensitive to the changes in exogenous N additions. In this paper, we conducted a 1,200-day in situ experiment in a typical semi-arid temperate steppe in Inner Mongolia to investigate the litter decomposition as well as the dynamics of litter C and N concentrations under three N addition levels (low N with 50 kg N/(hm2·a) (LN), medium N with 100 kg N/(hm2·a) (MN), and high N with 200 kg N/(hm2·a) (HN)) and three N addition forms (ammonium-N-based with 100 kg N/(hm2·a) as ammonium sulfate (AS), nitrate-N-based with 100 kg N/(hm2·a) as sodium nitrate (SN), and mixed-N-based with 100 kg N/(hm2·a) as calcium ammonium nitrate (CAN)) compared to control with no N addition (CK). The results indicated that the litter mass remaining in all N treatments exhibited a similar decomposition pattern: fast decomposition within the initial 120 days, followed by a relatively slow decomposition in the remaining observation period (120–1,200 days). The decomposition pattern in each treatment was fitted well in two split-phase models, namely, a single exponential decay model in phase I ( 398 days). The three N addition levels exerted insignificant effects on litter decomposition in the early stages ( 0.05). However, MN and HN treatments inhibited litter mass loss after 398 and 746 days, respectively (P 0.05). The effects of these two N addition forms differed greatly from those of CAN after 746 and 1,053 days, respectively (P 0.05). Our results indicated that exogenous N additions could exhibit neutral or inhibitory effects on litter decomposition, and the inhibitory effects of N additions on litter decomposition in the final decay stages are not caused by the changes in the chemical qualities of the litter, such as endogenous N and C concentrations. These results will provide an important data basis for the simulation and prediction of C cycle processes in future N-deposition scenarios.

The digital elevation model from the Shuttle Radar Topography Mission (SRTM) and the National Elevation Dataset (NED) have been used to estimate the forest canopy height. Most of such studies have been conducted over flat areas; the method performance has not been carefully examined over mountainous areas. This study, which is conducted over two mountainous test sites located in California and New Hampshire, reveals that the co-registration of these two digital elevation models (DEMs) is crucial to ensuring the quality of the results. The image co-registration method used in interferometric SAR processing is adapted to the co-registration of two DEMs. The forest canopy height from the Laser Vegetation Imaging Sensor (LVIS) is used as the reference data. The results showed that the misregistration between SRTM and NED was very obvious at both test sites. After the co-registration, the R2 of the correlation between the height of the C-band scattering phase center derived from SRTM minus NED and the forest canopy height derived from LVIS data was improved from 0.19 to 0.51, and RMSE was reduced from 16.4 m to 6.8 m for slope up to 55° at the California test site, while the R2 was improved from 0.39 to 0.57 and RMSE was reduced from 5.4 m to 3.6 m for slopes up to 45° at the New Hampshire test site. The influences of data resolution and terrain slopes were also investigated. The results showed that reducing the data resolution by spatial averaging could not reduce the influence of DEM misregistration.

Municipal solid wastes (MSW) have become an important factor constrainin China's economic, social and environmental development and affect the lives and health o residents nowadays, too. Therefore, how to effectively deal with the growing MSW has becom an important issue in China. This study shows that the main reasons leading to the dilemma o Chinese waste management are the unfair administrative way of solid waste management, the lack of economic incentives and the unfair recycling use and management.To solve thes problems, it is necessary to learn the experience from successful countries in wast management and to take policy measures from market-oriented operation, charging system producer responsibility, recycling scheme and so forth. At the same time, it is necessary activel to create conditions to bring government, residents and businesses together to realize the industrialization of China’s MSW disposal and virtuous circle.

Experimental autoimmune neuritis (EAN) is a CD4