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Abstract: In this study, physical and chemical characterizations of calcium methoxide were investigated to assess its performance as an excellent solid base catalyst using some instrumental methods, such as BET surface area measurement, scanning electron micrographs and particle size distribution. Then, it was used to catalyze transesterification of soybean oil to biodiesel with methanol. The effects of various factors such as mass ratio of catalyst to oil, reaction temperature and volume ratio of methanol to oil were studied to optimize the reaction conditions. The results showed that calcium methoxide has strong basicity and high catalytic activity as a heterogeneous solid base catalyst and it was obtained a 98% biodiesel yield within 2h in this reaction. Besides, the recycling experiment results showed it had a long catalyst lifetime and could maintain activity even after being reused for 20 cycles. [Copyright &y& Elsevier]

Abstract: In this study, transesterification of soybean oil to biodiesel using CaO as a solid base catalyst was studied. The reaction mechanism was proposed and the separate effects of the molar ratio of methanol to oil, reaction temperature, mass ratio of catalyst to oil and water content were investigated. The experimental results showed that a 12:1 molar ratio of methanol to oil, addition of 8% CaO catalyst, 65°C reaction temperature and 2.03% water content in methanol gave the best results, and the biodiesel yield exceeded 95% at 3h. The catalyst lifetime was longer than that of calcined K2CO3/γ-Al2O3 and KF/γ-Al2O3 catalysts. CaO maintained sustained activity even after being repeatedly used for 20 cycles and the biodiesel yield at 1.5h was not affected much in the repeated experiments. [Copyright &y& Elsevier]

Abstract: A laboratory investigation was performed to compare the fluxes of dinitrogen (N2), N2O and carbon dioxide (CO2) from no-till (NT) and conventional till (CT) soils under the same water, mineral nitrogen and temperature status. Intact soil cores (0–10cm) were incubated for 2 weeks at 25°C at either 75% or 60% water-filled pore space (WFPS) with 15N-labeled fertilizers (100mgNkg−1 soil). Gas and soil samples were collected at 1–4 day intervals during the incubation period. The N2O and CO2 fluxes were measured by a gas chromatography (GC) system while total N2 and N2O losses and their 15N mole fractions in the soil mineral N pool were determined by a mass spectrometer. The daily accumulative fluxes of N2 and N2O were significantly affected by tillage, N source and soil moisture. We observed higher (P<0.05) fluxes of N2+N2O, N2O and CO2 from the NT soils than from the CT soils. Compared with the addition of nitrate (NO3 −), the addition of ammonium (NH4 +) enhanced the emissions of these N and C gases in the CT and NT soils, but the effect of NH4 + on the N2 and/or N2O fluxes was evident only at 60% WFPS, indicating that nitrification and subsequent denitrification contributed largely to the gaseous N losses and N2O emission under the lower moisture condition. Total and fertilizer-induced emissions of N2 and/or N2O were higher (P<0.05) at 75% WFPS than with 60% WFPS, while CO2 fluxes were not influenced by the two moisture levels. These laboratory results indicate that there is greater potential for N2O loss from NT soils than CT soils. Avoiding wet soil conditions (>60% WFPS) and applying a NO3 − form of N fertilizer would reduce potential N2O emissions from arable soils. [Copyright &y& Elsevier]

Chinese agriculture represents one of the most intensively managed agroecosystems in the world. Typical nitrogen fertilization rates are more than three times those of the world' s average, resulting in dramatically accelerated nitrogen cycling in China. In this study, we have examined NO and N2O exchange in the upland agricultural systems of Beijing area. Inorganic and organic fertilizer treatments were arranged in order to evaluate their impact on the magnitude and proportion of trace gas emissions. Increasing inorganic fertilization rates showed a highly significant impact upon emissions of both NO and N2O. Organic matter amendment did not have a statistically significant impact on the N-gas fluxes examined here. Overall losses of added nitrogen by NO and N2O emission averaged 1. 24% and 0. 22% respectively over the range of treatments in this study. Results from our field study indicate that compared with other studies done elsewhere, emissions of reactive nitrogen from agricultural systems in Beijing area are not so large as expected before. [ABSTRACT FROM AUTHOR]

One of the obvious sources of errors in digital terrain analysis (DTA) algorithms is that introduced by raster data structure employed by a digital elevation model (DEM). Because of its regular sample space and orientation, the DTA results often show significant octant ‘bias’, presenting obvious visual and numerical error patterns. Moreover, other DEM data properties may also introduce errors in slope and aspect computation, such as data precision and spatial resolution (i.e. grid interval). This paper reports an investigation on the accuracy of algorithms that derive slope and aspect measures from grid DEM. A quantitative methodology has been developed for objective and data-independent assessment of errors generated from the algorithms that extract surface morphological parameters such as slope and aspect from grid DEM.The generic approach is to use artificial surfaces that can be described by a mathematical model, thus the ‘true’ output value can be pre-determined to avoid uncertainty caused by uncontrollable data errors. Two mathematical surfaces were generated based on ellipsoid (representing convex slopes) and Gauss synthetic surface (representing complex slopes), and the theoretical ‘true’ value of the slope and aspect at any given point on the surfaces could be computed using mathematical inference. Based on these models, tests were made on the results from a number of algorithms for slope and aspect computation. Analysis has been undertaken to find out the spatial and statistical patterns of error distribution so that the influence of data precision, grid resolution, grid orientation and surface complexity can be quantified. [Copyright &y& Elsevier]

Nitrogen dynamics and budgets in a clay loam soil (Meadow Aqualf) in the North China Plain were investigated in a winter wheat (Triticum aestivum L.) and maize (Zea mays L.) cropping system comparing the effects of four N rates (0, 120, 240 and 360 kg N ha−1 as urea) applied twice to each crop over 2 years. Ammonium nitrogen (NH4-N) in the soil profile remained at a low and constant level (except in the surface 20 cm layer) following application of fertilizer N. In contrast, nitrate nitrogen (NO3-N) levels were significantly altered by the rate of applied N. A strong tendency of NO3-N to move from the surface layer to the lower layers (20–100 cm) was observed during the wheat and maize growth seasons in treatments of 240 and 360 kg N ha−1 per crop (N240 and N360). The amounts of NO3-N accumulated in the soil profile were significantly higher in N240 and N360 than those in N0 and N120 (treatments receiving 0 and 120 kg N ha−1 per crop). After 2 years, soil NO3-N levels at 0–300 cm depth in N120, N240 and N360 amounted to 336, 815 and 1141 kg ha−1, respectively, with more than half of these amounts distributed in the 100–300 cm layer. The calculated total N balance indicates that most fertilizer N was available as NO3-N in the top 300 cm of the soil profile using traditional fertilization and irrigation practices. Over the subsequent 2 years, N losses were calculated to be relatively low in N120 but significantly higher in N240 and N360. Measured gaseous N losses showed that NH3 volatilization and denitrification comprised only a small fraction of total N losses during the 2-year rotation, while NO3-N leaching from the top 100 cm of the soil profile accounted for most N losses across all N rates and experimental years. The N budget showed that accumulation and/or leaching of NO3-N below 100 cm depth (beyond the reach of most roots) was the main pathway for N losses in the winter wheat–maize cropping system. The recommended N application rate of 120 kg N ha−1 minimized soil NO3-N accumulation and leaching losses while maintaining high yields and N utilization by winter wheat and maize. [Copyright &y& Elsevier]

The Clean Air Action implemented by the Chinese government in 2013 has greatly improved air quality in the North China Plain (NCP). In this work, we report changes in the chemical components of atmospheric fine particulate matter (PM 2.5) at four NCP sampling sites from 2012/2013 to 2017 to investigate the impacts and drivers of the Clean Air Action on aerosol chemistry, especially for secondary inorganic aerosols (SIA). During the observation period, the concentrations of PM 2.5 and its chemical components (especially SIA, organic carbon (OC), and elemental carbon (EC)) and the frequency of polluted days (daily PM 2.5 concentration ≥ 75 μg m−3) in the NCP, declined significantly at all four sites. Asynchronized reduction in SIA components (large decreases in SO 4 2− with stable or even increased NO 3 − and NH 4 +) was observed in urban Beijing, revealing a shift of the primary form of SIA, which suggested the fractions of NO 3 − increased more rapidly than SO 4 2− during PM 2.5 pollution episodes, especially in 2016 and 2017. In addition, unexpected increases in the sulfur oxidation ratio (SOR) and the nitrogen oxidation ratio (NOR) were observed among sites and across years in the substantially decreased PM 2.5 levels. They were largely determined by secondary aerosol precursors (i.e. decreased SO 2 and NO 2), photochemical oxidants (e.g. increased O 3), temperature, and relative humidity via gas-phase and heterogeneous reactions. Our results not only highlight the effectiveness of the Action Plan for improving air quality in the NCP, but also suggest an increasing importance of SIA in determining PM 2.5 concentration and composition. [Display omitted] • PM 2.5 and its chemical components were reduced in North China Plain during 2012–2017. • Reduced air pollutant emissions contributed more to PM 2.5 decline than meteorology. • NO 3 − became increasingly important in the formation of secondary inorganic aerosols. • Both sulfur oxidation ratio and nitrogen oxidation ratio increased unexpectedly. [ABSTRACT FROM AUTHOR]

• A method integrating the artificial neural network with genetic algorithm is proposed. • A three-dimensional multiphysics model is employed for data generation and validation. • The fuel cell maximum power and corresponding operation conditions are identified. • The maximum powers @ various temperatures & their operation conditions are identified. • Deep-learning results reflect major physical/electrochemical processes in fuel cells. The maximum achievable power of a polymer electrolyte membrane (PEM) fuel cell under specific operating temperature is important to its application. In this paper, we propose a method that integrates an artificial neural network (ANN) with the genetic algorithm (GA) to predict the performance of a PEM fuel cell and identify its maximum powers and corresponding conditions for operational control purpose. A validated three-dimensional (3D) multiphysics model is employed to generate total 1500 data points for training, testing, and verifying the ANN, which consists of two hidden layers with eight and four neurons on each hidden layer, respectively. After the ANN is properly trained, it is incorporated into the GA for deep learning to identify the maximum power and corresponding operating conditions, which shows that the fuel cell configuration could achieve a maximum power of about 0.78 W/cm2 at 368.8 K. Additionally, the combined ANN-GA method is employed to identify the maximum powers and their operating conditions under eight typical operation temperatures in the range of 323–373 K. The deep-learning results reflect the major physical and electrochemical processes that govern fuel cell performance and are validated against the 3D multiphysics model. The results demonstrate that the combined ANN-GA method is suitable to predicting fuel cell performance and identifying operation parameters for the maximum powers under various temperatures, which is important to practical system design and rapid control in fuel cell applications. [ABSTRACT FROM AUTHOR]

While many studies about gray water footprint (GWF) were carried out for different economic sectors, regions, production systems as well as methodologies, little research evaluates improving potential of the current situation. As the largest nitrogen (N) fertilizer consumption country in the world, leaching and runoff contributed half of the N release to waters, while associated GWF was not calculated based on local parameters, management and water quality standards. Different from previous studies, we firstly conducted a meta-analysis of N leaching and runoff parameters based on traditional and optimal management practices from the original field experiments rather than empirical parameters; then, distinguished the different influences of leaching and runoff on groundwater and surface water and applied corresponding standards for the GWF calculations; finally, estimated the improving potential of the GWF. The results show that N leaching and runoff could be reduced by 53%–84% and 34%–68%, respectively, by optimal fertilizer application and irrigation, and integrated management, while the corresponding GWF associated with leaching and runoff could be reduced by 53%–87% and 29%–59%, respectively, without sacrificing crop yields. The total GWF was 999.8 billion cubic meters in 2016, of which 45% was from leaching and 55% from runoff. GWF hotspots were concentrated in the middle and downstream of the Yangtze River basin, while the highest water pollution level (WPL) was found in northern China (e.g., in the Hai River basin, where N released to water exceeded the water resource dilution capacity). It was found that optimal fertilizer and irrigation management could reduce the GWF from existing cropping practices by 44%. We suggest that original experimental results and standards of different water pollution processes should be considered for the GWF calculations, and a GWF assessment under optimal crop management should be used as indicators to guide the technology and policy of water resource management and sustainable intensive agriculture development. • A meta-analysis based on traditional and optimal managements was conducted and applied for the improving potential of GWF. • Different influences on groundwater and surface water, combining local water quality standards were applied for assessment. • Improving potential should be highlighted as an indicator to guild water management and sustainable development. [ABSTRACT FROM AUTHOR]

The losses of excessive reactive nitrogen (N) from agricultural production pose detrimental impacts on water, air and land. However, N budgets of agroecosystems are still poorly quantified, presenting a barrier to understand the N turnover in agriculture. Agricultural ammonia (NH 3) volatilization has been recognized as a crucial contribution to the pollution of fine particulate matters over China through reacting with acid gases. Building on these challenges, the first national-scale model analysis was constructed on the N budgets to gain an overall insight into the current status of N flows in Chinese dryland systems towards sustainable N management. Total inputs of soil N in Chinese dryland soils were estimated at 121 kg N ha−1 in 2010, considering all pathways including N manure, fertilizer, atmospheric deposition and litter from crop residues. Atmospheric N deposition accounted for 25% of N fertilizer plus N manure in Chinese dryland soils, suggesting that N deposition could not be ignored when estimating total N inputs to Chinese dryland soils. The highest ratio of NH 3 volatilization to total N outputs was found at 43 kg N ha−1 (∼21%) in Northern China, followed by 41 kg N ha−1 (∼20%) in Sichuan Basin and 25 kg N ha−1 (∼26%) in Northeastern China. The modeling results indicated that, if a 20% decrease in N fertilizer plus N manure was achieved, it would lead to a 24% (7–49%) reduction in NH 3 volatilization. Substantial reductions of NH 3 volatilization would also be achieved by making an improvement in changing management practices (controlled release fertilizer and full irrigation). The results would give an overall insight into N budgets in Chinese dryland soils. The constructed N budgets assisted with understanding agricultural N flows and NH 3 pollution, and evaluated the impacts of human activities on N cycle towards a precise way to regulate agricultural management. Image 1 • N deposition accounted for 25% of N fertilizer in dryland soils. • NH 3 volatilizations were identified as the major pathways of soil N outputs. • NH 3 volatilizations can be reduced by appropriate fertilizer and irrigation. [ABSTRACT FROM AUTHOR]

Atmospheric reactive nitrogen (Nr) emissions and deposition have caused much damage to the global environment and also impacted human health. Determining long-term trends in atmospheric Nr concentrations and deposition is important for evaluating air quality and ecosystem effects and formulating control measures to reduce negative impacts. We measured monthly concentrations of NH 3 , pNH 4 +, HNO 3 , pNO 3 -, and NO 2 and calculated their dry deposition rates using an inferential method from 2011 to 2018 at an urban site in Zhengzhou in the North China Plain. Inorganic N (NH 4 + and NO 3 −) concentrations in precipitation and wet/bulk N deposition were also quantified in 2011, 2016, 2017 and 2018. The results showed high concentrations of atmospheric Nr species, with considerable variation in some species over the monitoring period. Annual mean NH 3 concentrations significantly increased from 2011 to 2018 (p < 0.001) with that in 2018 being twice that in 2011. However, pNO 3 - and pNH 4 + concentrations decreased after 2013. The annual mean NO 2 concentration in 2018 had decreased by 33.4% compared to the peak in 2011. Highest NH 3 concentrations were measured in spring or summer, and lowest concentrations in winter. pNH 4 + and pNO 3 - concentrations peaked mainly in winter. Total annual dry N deposition ranged from 21.9 to 41.2 kg N ha−1. Bulk NH 4 + and NO 3 − deposition was lower in 2016–2018 than in 2011. However, atmospheric Nr concentrations and N deposition remained high in this urban ecosystem. NH 3 emissions urgently need control measures, and Nr impacts on the surrounding ecosystems and human health should be considered. Continuous long-term measurements of atmospheric Nr concentrations and deposition at a regional scale are necessary to help formulate emission control measures and protect human and ecosystem health. • Significant changes in atmospheric reactive nitrogen were observed at an urban site in north China. • NH 3 concentrations increased by 110% from 2011 to 2018. • pNO 3 - and pNH 4 + concentrations in 2018 decreased by 65.1% and 62.8% compared to the maxima in 2012. • As a consequence, N deposition slightly decreased, with some improvement in air quality. [ABSTRACT FROM AUTHOR]

Distinct cropland acidification has been reported in China due to nitrogen (N) fertilizer overuse. However, the impacts on food production and thereby on food security are largely unknown. Yield losses in the period 1980–2050 were therefore assessed by simulating soil pH changes combined with derived pH-yield relationships for wheat, maize and rice. If the N fertilizer input continues to increase at 1% annually, the predicted average soil pH decline is about one unit and relative yield losses are expected to increase from approximately 4%–24% during 2010–2050. If the N fertilizer increase stops in 2020 (N2020), the expected losses are approximately 16% in 2050, which is comparable to a scenario of 100% crop residue return (100%RR). However, if 30% of the N fertilizer is replaced by manure N (30%MR), the losses reduce to near 5% in 2050. Soil acidification was predicted to reverse and expected losses are only 2.5% in 2050 in a combined scenario of N2020, 100%RR and 30%MR. Our results illustrate the potential food insecurity induced by cropland acidification and address the necessity of mitigation. Image 1 • Yield losses due to cropland acidification were assessed in China. • Expected yield losses are about 24% at 2050 if current N fertilizer rates are continued. • The current policy of stopping N fertilizer increase is not enough to avert the yield losses. • Replacement of N fertilizer by manure is an effective way to reduce acidification. • Induced food insecurity can be eliminated by an appropriate fertilizer management strategy. Possible future cereal losses induced by cropland acidification and resulting food security were assessed on national level to address the necessity of mitigation. [ABSTRACT FROM AUTHOR]

It is of significant importance to construct the low-cost, efficient, and stable carbon-based non-noble metal to replace the noble metal electrocatalyst for oxygen reduction reaction in both alkaline and acidic media. In this work, a straightforward and cost-efficient strategy is reported to synthesize the Fe–N co-doped open-porous carbon materials with three-dimensional (3D) carbon networks structure, high surface areas and multiple actives sites including iron carbide nanoparticles, pyridinic N, and graphitic N using a new kind of Fe-Imace coordinated complex as the precursor and melamine as nitrogen sources by direct pyrolysis. The obtained Fe– N –C 900 catalyst shows excellent oxygen reduction performance in both alkaline (E onset , 1.014 vs. RHE) and acidic (E onset , 0.982 V vs. RHE) media, which are better than those of the Pt/C in alkaline (E onset , 0.986 vs. RHE) and acidic media (E onset , 0.979 V vs. RHE). Even more important, the stability and methanol tolerance of the Fe–N–C 900 catalyst are much better than that of the Pt/C catalyst in both alkaline and acidic media. All the results demonstrate that the present facile and universal one-step pyrolytic strategy can be used to synthesize catalyst materials as one of the superior non-precious cathode electrocatalysts for fuel cells. [Display omitted] • 3D hierarchical open-porous carbon networks catalyst (Fe– N –C) is obtained by one-step pyrolytic method. • Fe 3 C nanoparticle plays a crucial role in improving the activity of Fe– N –C. • The synthesized Fe– N –C 900 catalyst exhibits excellent ORR activity and stability in alkaline and acidic media. [ABSTRACT FROM AUTHOR]

In a recent publication in the journal Science of the Total Environment, Zhu et al. (2015) reported the composition, spatial patterns, and factors influencing atmospheric wet nitrogen (N) deposition based on one year's data from 41-monitoring sites in China. We suspect their results may largely underestimate dissolved organic N (DON) but overestimate total particulate N (TPN) in wet deposition due to the uncertainty resulting from the sampling, storage and analysis methods in their study. Our suspicions are based mainly on our experience from earlier measurements and the literature. We therefore suggest that enhanced data quality control on atmospheric N deposition measurements should be taken into account in future studies. [ABSTRACT FROM AUTHOR]

The effects of substituting pork lean meat with Lentinula edodes (LE) on the physicochemical properties, amino acid content, cooking loss, texture, total phenolic content, antioxidant activity, microstructure, microbiological analysis, and sensory characteristics of sausages were evaluated. Five formulations were used in the production of sausages: the control (the pork lean meat formulation) and the four different samples in which LE substituted 25%, 50%, 75%, and 100% of pork lean meat. The results showed that LE improved the moisture, total dietary fiber, methionine, glutamic, cysteine, and total phenolic content; cooking loss; and antioxidant activity of the sausage. By contrast, LE reduced the levels of protein, ash, pH, as well as the energy level and texture of the sausage. No difference was observed between the treatments for fat content, water activity and microorganisms of sausages. In addition, LE led to slight darkening of the sausages. From the sensory point of view, all modified sausages were considered acceptable, and the pork lean meat with 25% substitution by LE exhibited best sensory characteristics. In a word, LE is a promising ingredient to partially replace the lean meat in sausages. • Lentinula edodes (LE) as a kind of pork lean meat replacer was used in sausage production. • LE improved the moisture, total dietary fiber, methionine, glutamic and cysteine content of the sausage. • The substitution of pork lean meat by LE reduced the energy value of the sausage. • LE enhanced total phenolic content and antioxidant activity of the sausage. [ABSTRACT FROM AUTHOR]

Abstract While the ongoing increases in the deposition of atmospheric nitrogen (N) in China have attracted ever more attention, to date there has been little research in N deposition in inland aquatic ecosystems. In this study, we quantified the bulk and dry atmospheric N deposition around the Dongting Lake, which is connected to the Yangtze River and is the second largest freshwater lake in China. Bulk N deposition averaged 48.0 kg N ha−1 yr−1, of which ammonium (NH 4 N), nitrate (NO 3 N), and dissolved organic nitrogen (DON) accounted for 41.6%, 35.1%, and 23.3%, respectively. Dry N deposition averaged 27.0 kg N ha−1 yr−1, and was dominated by NH 3. Bulk N deposition was higher in spring and summer than in autumn and winter at the sites around the lake because of the high precipitation. NH 3 deposition was the highest in spring and summer due to fertilization, and NO x deposition was the highest in winter because of the combustion of coal for domestic heating. The concentrations of NH 3 significantly decreased with the concentration of NH 4 N, indicating below-cloud scavenging and local sources. The concentrations of NO x and NO 3 N were not correlated, indicating long-distance transfer of NO x. Bulk N deposition in our study was generally twice that reported in other studies, even when only inorganic N species in bulk deposition were considered. Total N deposition averaged 75.0 kg N ha−1 yr−1, which was much higher than that reported in other studies. Both N deposited directly into the lake and N deposited across the lake basin that was subsequently transported to the lake in runoff could enrich the N concentration of the lake water and increase the gross primary productivity (GPP). Our results highlighted the importance of integrated management that includes both aquatic and atmospheric systems at either the lake basin scale or regional scale, rather than at the individual lake-scale. Graphical abstract Image 1 Highlights • Total N deposition was much higher than that reported in other studies around the Dongting Lake. • DON deposition, which usually be ignored, is a significant contributor. • Potential eutrophication effects of N loading to the Dongting Lake from atmospheric N deposition should be re-evaluated. [ABSTRACT FROM AUTHOR]

Abstract Education is the foundation and strength of a nation, and educational equity is the basic right of every citizen. However, in China, there are vast differences in education levels between the eastern and western areas, urban and rural areas, and ethnic and non-ethnic areas. This is especially so in China's mountainous areas in the rural southwest. In this region, Yunnan Province is selected as study area. This study proposed an educational convenience index (ECI), and established an evaluation model for educational convenience in mountainous regions. In this model, we investigated the road networks that connect settlements to schools in ethnic mountainous areas, and considered the vulnerability, complexity and accessibility of the road networks from settlements to schools. In road vulnerability analysis, a new concept of "only link" is introduced. Based on this model, the ECI of each settlement in Yunnan Province in 2011 and 2015 was calculated. The improvement of ECI for each settlement in the 4-year period between 2011 and 2015 was analyzed. The findings show that: (1) Educational convenience of non-ethnic autonomous regions (65% settlements >=" good") was far better than that of ethnic autonomous regions (53% settlements >= "good"). (2) The educational convenience level in both ethnic and non-ethnic autonomous regions have improved. The improvement was slightly lower in ethnic autonomous regions (5.44%) than in non-ethnic autonomous regions (6.23%). (3) The comparison of improvements in educational convenience between 2011 and 2015 showed that such improvements formed a significant "substantially improved - greatly improved - moderately improved" three-tier pattern and a "greatly improved - moderately improved" two-tier pattern. Highlights • Propose an educational convenience index of the settlements in ethnic mountainous areas. • Establish an evaluation model based on the vulnerability of road network. • Educational convenience of non-ethnic regions was far better than that of ethnic regions in 2015. • Educational convenience in ethnic and non-ethnic regions was improved in 2011–2015. [ABSTRACT FROM AUTHOR]

Significant soil pH decrease has been reported in Chinese croplands in response to enhanced chemical fertilizer application and crop yields. However, the temporal and spatial variation of soil acidification rates across Chinese croplands is still unclear. We therefore assessed trends in soil acidification rates across provincial China for the period 1980–2010 by calculating inputs-outputs of major cations and anions in cropland systems. Nitrogen (N) induced proton production increased from 4.7 keq H + /ha/yr in 1980 to a peak of 11.0 keq H + /ha/yr in 1996 and remained nearly constant after 2000 at a rate of approximately 8.6 keq H + /ha/yr. The proton production induced by crop removal increased from 1.2 to 2.3 keq H + /ha/yr. The total proton production thus increased from 5.9 to 10.9 keq H + /ha/yr in the 30 years. As a result, the actual acidification rate, reflected by (base) cation losses, accelerated from 2.3 to 6.2 keq H + /ha/yr and the potential acidification rate, reflected by phosphorus accumulation accelerated from 0.2 to 1.3 keq H + /ha/yr. The national averaged total acidification rates were thus estimated to increase from 2.6 to 7.6 keq H + /ha/yr in the past 30 years. The highest soil acidification rate occurred in the Jiangsu Province with a rate of 17.9 keq H + /ha/yr, which was due to both high N application rates and high base cation removals by crops and crop residues. The combination of elevated N inputs and decreased N use efficiency (NUE) in response to those N inputs, thus enhancing the nitrate discharge, were the main reasons for the accelerated acidification in Chinese croplands. Considering the expected growth of food demand in the future, and the linkage between grain production and fertilizer N consumption, a further acceleration of soil acidification can thus be expected, unless the N inputs is reduced and/or the NUE is increased substantially. [ABSTRACT FROM AUTHOR]

Background: H1-receptor inverse agonists are used effectively for treating several symptoms of allergic rhinitis, including nasal itching, rhinorrhea, and sneezing, although most agents are not very effective in treating nasal congestion. Objective: This study evaluated the relative efficacy of a novel selective H3-receptor antagonist, JNJ-39220675, in preventing nasal congestion induced by exposing participants with ragweed allergy to ragweed allergen in an environmental exposure chamber model. Methods: In this single-dose, patient-blind, double-dummy, placebo- and active-controlled, phase IIa cross-over study, 53 participants were randomized to JNJ-39220675 plus placebo, placebo plus pseudoephedrine, or only placebo. The primary efficacy assessment was change in nasal patency assessed by measuring the minimal cross-sectional area of the nasal cavity by using acoustic rhinometry. Secondary assessment included total nasal symptom scores (TNSSs) over the 8-hour environmental exposure chamber exposure period. Results: Smaller decreases in minimal cross-sectional area were observed after JNJ-39220675 (least square mean difference, −0.126; P = .06) and pseudoephedrine (least square mean difference, −0.195; P = .004) treatment compared with placebo. The means for the baseline-adjusted area under the curve of TNSSs were significantly smaller for JNJ-39220675 (P = .0003) and pseudoephedrine (P = .04) versus placebo. JNJ-39220675 was significantly effective in treating all 4 individual symptoms (P ≤ .05 for all scores) compared with placebo, whereas pseudoephedrine only showed a trend for improvement in individual symptom scores of the TNSS. Insomnia was the most frequent adverse event (17.3%) associated with JNJ-39220675 treatment. Conclusion: Prophylactic treatment with the H3-antagonist JNJ-39220675 relieved allergen-induced nasal congestion by using standard nasal symptom scoring; however, in contrast to pseudoephedrine, it only showed a trend for increasing nasal patency by using objective measures. [Copyright &y& Elsevier]

Soils below croplands and grasslands have acidified significantly in China since the 1980s in terms of pH decline in response to acid inputs caused by intensified fertilizer application and/or acid deposition. However, it is unclear what the rate is of pH decline of forest soils in China in response to enhanced acid deposition and wood production over the same period. We therefore gathered soil pH data from the Second National Soil Inventory of China and publications from the China National Knowledge Infrastructure (CNKI) database in 1981–1985 and 2006–2010, respectively, to evaluate the long-term change of pH values in forest soils. We found that soil pH decreased on average by 0.36 units in the period 1981–1985 to 2006–2010., with most serious pH decline occurring in southwest China (0.63 pH units). The soil type with the strongest pH decline was the semi-Luvisol (0.44 pH units). The decrease in pH was significantly correlated with the acid input induced by atmospheric deposition and forest harvesting. On average, the contribution of atmospheric deposition to the total acid input was estimated at 84% whereas element uptake (due to forest wood growth and harvest) contributed 16% only. Atmospheric deposition is thus the major driver for the significant forest soil acidification across China. [ABSTRACT FROM AUTHOR]

Patients with venous thromboembolism (VTE) and cancer are at higher risk of recurrent VTE and mortality. Clinical guidelines recommend anticoagulant treatment for these patients. This study assessed trends in outpatient anticoagulant treatment and factors associated with this treatment initiation in outpatient setting among this high-risk patient population. To study trends and factors associated with anticoagulant treatment initiation among patients with VTE and cancer. VTE cancer patients age ≥65 were identified from the SEER-Medicare database from 01JAN2014-31DEC2019. Patients were enrolled for ≥6 months prior to their first VTE (i.e. index event) and without evidence of other reasons for anticoagulation (i.e., atrial fibrillation). Patients were also required to be enrolled for ≥30 days after index. Cancer status was identified from SEER or Medicare database in the 6 months pre- through 30 days post-VTE. Patients were classified into treated or untreated cohorts depending on whether they initiated outpatient anticoagulant treatment within 30 days post-index. The trends of treated vs. untreated were evaluated by quarter. Logistic regression was used to identify demographic-, VTE-, cancer- and comorbid-related factors associated with anticoagulant treatment initiation. A total of 28,468 VTE-cancer patients met all study criteria. Of these, ~46 % initiated outpatient anticoagulant treatment within 30 days, and ~54 % did not. The above rates were stable from 2014 to 2019. Factors such as VTE diagnosis in inpatient setting, pulmonary embolism (PE) diagnosis, and pancreatic cancer were associated with increased odds whereas bleeding history and some comorbid factors were associated with decreased odds of initiating anticoagulant treatment. Over half of VTE patients with cancer did not initiate outpatient anticoagulant treatment within the first 30-days after VTE diagnosis. This trend was stable from 2014 to 2019. A range of cancer-, VTE-, and comorbid-related factors were associated with the likelihood of the treatment initiation. • Over half of patients did not initiate anticoagulant treatment within 30 days as recorded. • Rates of anticoagulant treatment initiation remained stable over time. • Several factors were associated with initiating anticoagulant treatment. • A switch to new anticoagulants such as apixaban was observed over time. [ABSTRACT FROM AUTHOR]

Quantifying the similarities and differences in atmospheric nitrogen (N) deposition between different ecosystems is important to develop effective measures to reduce air pollution and maintain biodiversity. Here we show that the constitution of N deposition differed significantly between a grassland and a desert ecosystem in Northwestern China. Flux of bulk (wet plus part of dry deposition) and dry (gaseous NH 3 and NO 2) deposition were continuously monitored from 2018 to 2020. The grassland and desert sites had similar amount of total N deposition, being 7.29 and 6.33 kg N ha−1 yr−1, respectively. However, N deposition at the grassland was dominated by the bulk deposition (4.44 kg N ha−1 yr−1, 61% of the total N deposition), whereas that at the desert was dominated by dry deposition (4.20 kg N ha−1 yr−1, 66% of total deposition). The desert had greater ambient concentrations of NH 3 (3.66 μg N m−3) and NO 2 (1.52 μg N m−3) than the grassland (2.73 μg NH 3 –N m−3 and 0.72 μg NO 2 –N m−3). The amount of reduced N deposition (NH 4 + and NH 3) was around 3 times of that of oxidized N deposition (NO 3 − and NO 2) in both ecosystems. The N deposition rates in both ecosystems have exceeded the critical load for the fragile ecosystems (5–10 kg N ha−1 yr−1), highlighting the importance of reducing N emission sources that are related with anthropogenic disturbance. [Display omitted] • The boundary of Tarim Basin and Tibet Plateau has relatively low N deposition. • Bulk and dry deposition dominated in grassland and desert, respectively. • The reduced/oxidized N ratio in N deposition was close to 3 in both ecosystems. • N deposition exceeded the minimum critical load value for sensitive ecosystems. [ABSTRACT FROM AUTHOR]

We investigated variations of PM 2.5 and water-soluble inorganic ions chemical characteristics at nine urban and rural sites in China using ground-based observations. From 2015 to 2019, mean PM 2.5 concentration across all sites decreased by 41.9 µg/m3 with a decline of 46% at urban sites and 28% at rural sites, where secondary inorganic aerosol (SIAs) contributed to 21% (urban sites) and 17% (rural sites) of the decreased PM 2.5. SIAs concentrations underwent a decline at urban locations, while sulfate (SO 4 2–), nitrate (NO 3 –), and ammonium (NH 4 +) decreased by 49.5%, 31.3% and 31.6%, respectively. However, only SO 4 2– decreased at rural sites, NO 3 – increased by 21% and NH 4 + decreased slightly. Those changes contributed to an overall SIAs increase in 2019. Higher molar ratios of NO 3 – to SO 4 2– and NH 4 + to SO 4 2– were observed at urban sites than rural sites, being highest in the heavily polluted days. Mean molar ratios of NH 3 /NH x were higher in 2019 than 2015 at both urban and rural sites, implying increasing NH x remained as free NH 3. Our observations indicated a slower transition from sulfate-driven to nitrate-driven aerosol pollution and less efficient control of NO x than SO 2 related aerosol formation in rural regions than urban regions. Moreover, the common factor at urban and rural sites appears to be a combination of lower SO 4 2– levels and an increasing fraction of NO 3 – to PM 2.5 under NH 4 +-rich conditions. Our findings imply that synchronous reduction in NO x and NH 3 emissions especially rural areas would be effective to mitigate NO 3 –-driven aerosol pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

Airfoil design based on Bayesian optimization generally involves high-fidelity simulations, whose crux in terms of efficiency has always challenged existing optimization frameworks. Theoretically, fully mining the useful information in the evaluated samples is expected to speed up the optimization process. In this paper, a multi-objective Bayesian optimization framework explicitly modeling objective correlations is proposed for airfoil design to make the most of the expensive simulations, where a convolved multiple output Gaussian process (CMOGP) surrogate model and a correlated Pareto-frontier entropy search (cPFES) infill sampling strategy are incorporated respectively for reliable capture of the complex relationships involved and final acquisition of well-distributed Pareto airfoils. Specially, a correlation-concerned representative Pareto-frontier sampling method is also proposed to guide candidate selection in cPFES to a prospective optimization direction efficiently. Comparative results on synthetic problems and an airfoil aerodynamic-stealth design problem demonstrate that modeling objective correlations contributes to both the improvement in prediction accuracy for promising regions and the accelerated convergence to a superior and well-distributed Pareto-frontier within a limited budget. It indicates potential practicability of the proposed framework for multi-objective airfoil design as well as other engineering optimization problems to alleviate efficiency issues. [ABSTRACT FROM AUTHOR]

The molecular geometries, FT-IR and Raman spectra of 2-acetylpyridine were studied using Density functional theory (DFT-B3LYP) with the large basis sets. Theoretical calculations indicate the cis conformer of 2-acetylpyridine is most stable though this conformation was seldom found in the crystal structures of coordinated compounds. Based on the stable conformer, comprehensive assignments of the experimental bands were made. The observed and calculated positions are found to be in good agreement with an average deviation of <4 cm −1 . The assignments provide valuable information for the fingerprint and identification of 2-acetylpyridine. [ABSTRACT FROM AUTHOR]

Abstract: We research an efficient BER estimation method for 112-Gb/s polarization division multiplexing coherent optical OFDM (PDM CO-OFDM) with QPSK mapping over 800km SSMF based on Eb/No algorithm in this paper. We first lay out the related formulas’ derivation to set up the theoretical basis for the feasibility of Eb/No algorithm and then we implement a series of simulations to illustrate the relationship of BER (and Q factor) versus OSNR, launch power of transmitter, chromatic dispersion and nonlinearity in optical fiber link via both Eb/No algorithm and Monte Carlo algorithm. The simulations demonstrate that BER estimated by Eb/No algorithm can achieve a precision up to 10−16 just with 105 bits while Monte Carlo algorithm needs at least 1018 bits to get the same level. Therefore, Eb/No allows a quick and reliable method for BER estimation instead of the time consuming Monte Carlo method, which can be used to support simulations with various conditions. [Copyright &y& Elsevier]

Abstract: The calculation of contributing areas from digital elevation models (DEMs) is one of the important tasks in digital terrain analysis (DTA). The computational process usually involves two steps in a real application: (1) calculating flow directions via a flow model, and (2) computing the contributing area for each grid cell in the DEM. The traditional algorithm for calculating contributing areas is coded as a sequential program executed on a single processor. With the increase of scope and resolution of DEMs, the serial algorithm has become increasingly difficult to perform and is often very time-consuming, especially for DEMs of large areas and fine scales. In recent years, parallel computing is able to meet this challenge with the development of computer technology. However, the parallel implementation with granularity control, an efficient strategy to reap the best parallel performance and to break the limitation of computing resources in processing massive grid terrain datasets, has not been found in DTA research field. This paper develops a message-passing-interface (MPI) parallel approach with granularity control to calculate contributing areas. According to the proposed parallelization strategy, the parallel D8 algorithm with granularity control is designed as well as the parallel AreaD8 algorithm. Based on the domain decomposition of DEM data, it is possible for each process to process multiple partitions decomposed under a grain size. According to an iterative procedure of reading source data, executing the operator and writing resulting data, the partitions achieve the calculation results one by one in each process. The experimental results on a multi-node cluster show that the proposed parallel algorithms with granularity control are the powerful tools to process the big dataset and the parallel D8 algorithm is insensitive to granularity, while the parallel AreaD8 algorithm has an optimal grain size to reap the best parallel performance. [Copyright &y& Elsevier]

Abstract: Atmospheric emissions of reactive nitrogen (N) species are at high levels in China in recent years, but few studies have employed N deposition monitoring techniques that measure both dry and wet deposition for comprehensive evaluation of the impacts of N deposition on ecosystems. In this study, to quantify the total N deposition, both dry and wet N depositions were monitored using denuder/filter pack systems, passive samplers and wet-only samplers at three sites with different land use types (forest, paddy field and tea field) in a 135-km2 catchment in subtropical central China from September 2010 to August 2011. At the three sampling sites, the annual mean concentrations of total N (the sum of , and DON) in rainwater were 1.2–1.6 mg N L−1, showing small variation across sites. Annual mean concentrations of total N (the sum of NH3, NO2, HNO3, particulate and ) in the air were 13–18 μg N m−3. High NH3 concentrations in the air were observed at the agricultural sites of tea and paddy fields, indicating significant NH3 emissions from N fertiliser application; and high NO2 concentrations were found at the upland sites of forest and tea field, suggesting high NO emissions from soils due to high N deposition or high N fertiliser input. The annual total N deposition for the three sites of paddy field, tea field and forest was estimated as 22, 34 and 55 kg N ha−1 yr−1, in which the dry N deposition components contributed to 21%, 36% and 63% of the annual total N deposition, respectively. The annual deposition of reduced N species was 1.1–1.8 times of the annual deposition of oxidised N species. To minimise the adverse effects of atmospheric N deposition on natural/semi-natural ecosystems, it is crucial to reduce the reactive N emissions from anthropogenic activities (e.g., N fertiliser application, animal production and fossil fuel combustion) in subtropical central China. [Copyright &y& Elsevier]

Abstract: Perturbation and observation (P&O) maximum power point tracking (MPPT) algorithms are common in photovoltaic (PV) systems due to its ease of implementation. However, operation with fixed size perturbations results in a trade-off between speed of response and maximum power yield in the steady-state. This paper discusses the use of Fuzzy logic and non-switching zone schemes for implementing variable size perturbations for improved transient and steady-state responses. The potential performance of four different P&O algorithms is investigated by means of simulations. Experimental results are then used to verify how the computational burden of each algorithm and the processing speed of a digital signal processor (DSP) affect the performance of each method in a prototype. The best performance is achieved with a new strategy called non-switching zones in the V PV × I PV plane. The power electronics converter operates with duty cycle (D) equal to 0 or 1, depending on which non-MPP region the system operates, pushing the operating point the fastest way possible towards the MPP region, for improved transient response. At the MPP region, a reduced Fuzzy P&O MPPT algorithm optimized for small variations around the MPP is used for reduced oscillations and increased power yield in the steady-state. [Copyright &y& Elsevier]

Environmental audio recordings are a rich and underexploited source of rainfall events. Widespread surveillance cameras continuously record rainfall information, which provides a basis for the possibility of rainfall monitoring. In this study, using surveillance audio as input, an automatic rainfall level classification system was built. Through rainfall level definitions, the rainfall observation task can be transformed into an audio classification task. Three 2-D baseline convolutional neural networks (CNNs) were proposed as the classifiers. In view of the classifier training and testing, a new dataset named Rainfall Audio_XZ (RA_XZ) was generated based on the surveillance audio data. Because of the significant impact of the input features on the classification performance, 16 kinds of feature aggregation schemes were constructed and investigated to find the best representation of rainfall. The experimental results demonstrate that the proposed CNN (7-stack CNN) achieves 81.67% accuracy in rainfall level classification in the RA_XZ dataset and 93.38% accuracy in environmental sound classification in the UrbanSound8k dataset, which is optimal performance compared to that of some existing relevant algorithms. Furthermore, audio aggregation strategies that facilitate the representation and classification of rainfall events are investigated, which has important implications for audio and speech classification systems. In summary, our study provides an effective supplement to traditional rainfall monitoring technologies. [ABSTRACT FROM AUTHOR]

Organic nitrogen (N) is an important component of the atmospheric deposition of reactive N, but its sources are essentially unknown. Assessing whether this dissolved organic N (DON) is of natural, anthropogenic or mixed origin is critically important in attempting to determine the scale of human perturbation of the global N cycle. Here we report evidence for atmospheric organic N deposition and its anthropogenic sources in China. Precipitation samples were collected and analyzed from 15 rural, suburban and urban sites during 2005 and 2006. The average deposition of DON was 8.6kgha−1 yr−1 with a volume-weighted concentration of 111μmolL−1, which was much higher than in other regions of the world. The contribution of DON to total dissolved N (TDN) was approximately 30% on average, agreeing well with other reported data in the literature. Parallel collections of wet-only and bulk deposition showed wet deposition to be 68% on average, indicating a significant dry deposition component. Combining data from the Chinese sites with those from elsewhere in the world, significant (p<0.0001) correlations between DON and NH4–N, NO3–N and TDN suggest that atmospheric organic N originates from similar sources to dissolved inorganic N (DIN) (NH4–N and NO3–N), which are largely attributed to anthropogenic emissions from both agricultural and industrial sources. [Copyright &y& Elsevier]

Abstract: A 3-year field experiment examined the effects of non-flooded mulching cultivation and traditional flooding and four fertilizer N application rates (0, 75, 150 and 225kgha-1 for rice and 0, 60,120, and 180kgNha-1 for wheat) on grain yield, N uptake, residual soil Nmin and the net N balance in a rice–wheat rotation on Chengdu flood plain, southwest China. There were significant grain yield responses to N fertilizer. Nitrogen applications of >150kgha-1 for rice and >120kgha-1 for wheat gave no increase in crop yield but increased crop N uptake and N balance surplus in both water regimes. Average rice grain yield increased by 14% with plastic film mulching and decreased by 16% with wheat straw mulching at lower N inputs compared with traditional flooding. Rice grain yields under SM were comparable to those under PM and TF at higher N inputs. Plastic film mulching of preceding rice did not affect the yield of succeeding wheat but straw mulching had a residual effect on succeeding wheat. As a result, there was 17–18% higher wheat yield under N0 in SM than those in PM and TF. Combined rice and wheat grain yields under plastic mulching was similar to that of flooding and higher than that of straw mulching across N treatments. Soil mineral N (top 60cm) after the rice harvest ranged from 50 to 65kgha-1 and was unaffected by non-flooded mulching cultivation and N rate. After the wheat harvest, soil Nmin ranged from 66 to 88kgNha-1 and increased with increasing fertilizer N rate. High N inputs led to a positive N balance (160–621kgha-1), but low N inputs resulted in a negative balance (-85 to -360kgha-1). Across N treatments, the net N balances of SM were highest among the three cultivations systems, resulting from additional applied wheat straw (79kgha-1) as mulching materials. There was not clear trend found in net N balance between PM and TF. Results from this study indicate non-flooded mulching cultivation may be utilized as an alternative option for saving water, using efficiently straw and maintaining or improving crop yield in rice–wheat rotation systems. There is the need to evaluate the long-term environmental risks of non-flooded mulching cultivation and improve system productivity (especially with straw mulching) by integrated resource management. [Copyright &y& Elsevier]

The significant progress of non-precious metal cathodic electrocatalytic materials is impressive in electrochemical energy conversion application. Here, iron and nitrogen co-doped porous carbon spheres (Fe/N-PCS) have been designed via 3-aminophenol/formaldehyde (APF) resin spheres as carbon precursor, ferric nitrate as iron source, colloidal silica as template and tetramethylguanidine as catalyst by the improved Stöber method. Fe/N-PCS possesses uniform spherical morphology, abundant mesoporous shape and high surface area and exhibits higher oxygen reduction reaction (ORR) electrocatalytic activity (E 1/2 , 0.838 V vs. RHE) compared with the Pt/C (E 1/2 , 0.827 V vs. RHE) in alkaline media. In addition, the methanol tolerance and catalytic stability of Fe/N-PCS are greater than commercial Pt/C catalyst. The outstanding ORR behavior of Fe/N-PCS mainly benefits from the iron and nitrogen elements synergistic effect, pyridinic N and the spherical porous structure enabling plenty of active sites exposed. This method is prospective for preparation of highly efficient cathodic ORR electrocatalyst. [Display omitted] • Fe-N co-doped porous carbon spheres (Fe/N-PCS) are obtained by an improved Stöber method. • The synergistic effect between iron and nitrogen species dopant can facilitate ORR activities. • The Fe/N-PCS catalyst exhibits excellent ORR activity and stability in alkaline media. [ABSTRACT FROM AUTHOR]

[Display omitted] • Personal exposure to particulate and gaseous pesticides was characterized. • Particulate/gaseous distribution of pesticides was studied in indoor-outdoor nexus. • Two third of exposed pesticides mainly originated from non-occupational sources. • Over 43% of bystanders suffered the same exposure level as farmers. • Around 7% and 3% of local farmers and bystanders may suffer chronic health risk. Rural residents are exposed to both particulate and gaseous pesticides in the indoor-outdoor nexus in their daily routine. However, previous personal exposure assessment mostly focuses on single aspects of the exposure, such as indoor or gaseous exposure, leading to severe cognition bias to evaluate the exposure risks. In this study, residential dust and silicone wristbands (including stationary and personal wearing ones) were used to screen pesticides in different phases and unfold the hidden characteristics of personal exposure via indoor-outdoor nexus in intensive agricultural area. Mento-Carlo Simulation was performed to assess the probabilistic exposure risk by transforming adsorbed pesticides from wristbands into air concentration, which explores a new approach to integrate particulate (dust) and gaseous (silicone wristbands) pesticide exposures in indoor and outdoor environment. The results showed that particulate pesticides were more concentrated in indoor, whereas significantly higher concentrations were detected in stationary outdoor wristbands (p < 0.05). Carbendazim and chlorpyrifos were the most frequently detected pesticides in dust and stationary wristbands. Higher pesticide concentration was found in personal wristbands worn by farmers, with the maximum value of 2048 ng g−1 for difenoconazole. Based on the probabilistic risk assessment, around 7.1 % of farmers and 2.6 % of bystanders in local populations were potentially suffering from chronic health issues. One third of pesticide exposures originated mainly from occupational sources while the rest derived from remoting dissipation. Unexpectedly, 43 % of bystanders suffered the same levels of exposure as farmers under the co-existence of occupational and non-occupational exposures. Differed compositions of pesticides were found between environmental samples and personal pesticide exposure patterns, highlighting the need for holistic personal exposure measurements. [ABSTRACT FROM AUTHOR]

Plant straw resources are rich, and the annual yield of crop straw is large. To reduce environmental pollution caused by the burning of plant straw and realize maximum resource utilization of straw, the published literature data are analyzed in depth. It was found that the carbon element content in the straw was about 40% and the ash content was low. The straw activated carbon can meet the adsorption standard requirements of wooden activated carbon, which was a good material for the sustainable utilization of activated carbon. The activated carbons prepared from cotton straw and hemp straw have large specific surface area, and the total pore volumes of activated carbon from sunflower straw and hemp straw are obviously higher than that of other straw activated carbon. In order to improve the quality of activated carbon, the effects of various activators are better than that of single activator in the preparation of straw activated carbon. The study found that when the ratio of the initial concentration of pollutants to the adsorbent concentration is 30, the removal efficiencies of heavy metals (Cu(II), Cr(VI) and Fe(III)) aren't less than 90%. This review will be of great significance to optimize the preparation conditions of straw activated carbon, improve the quality of straw activated carbon and expand the application range of straw activated carbon. • The C element content of straw is approximately 40%. • Most of straw AC can meet the standard requirements of wooden AC. • The removal rates of heavy metals (Cu(II), Cr(VI) and Fe(III)) exceeded 90% (K < 30). • Straw AC has more advantages than coal-based AC. • The economic and environmental benefits of straw AC are better than other AC. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy (DN) is now considered the leading cause of end-stage renal disease. In diabetes, the accumulation of reactive oxygen species (ROS) and iron overload are important determinants that promote the occurrence of DN. However, the underlying mechanism of how they cause diabetic kidney damage remains unclear. Ferroptosis, characterized by iron-dependent lipid peroxidation, provided us with a new idea to explore the progression of DN. Iron overload, reduced antioxidant capability, massive ROS and lipid peroxidation were detected in the kidneys of streptozotocin-induced DBA/2J diabetic mice and high-glucose cultured human renal proximal tubular (HK-2) cells, which were the symbolic changes of ferroptosis. Furthermore, the characteristic mitochondrial morphological changes of ferroptosis were observed in high glucose cultured cells. Additional treatment of Ferrostatin-1 (Fer-1) in DN models significantly rescued these changes and alleviated the renal pathological injuries in diabetic mice. Besides, the decreased NFE2-related factor 2 (Nrf2) was observed in DN models. The specific knockdown of Nrf2 increased the sensitivity of cells to ferroptosis in the high glucose condition. In Nrf2 knockdown cells, up-regulating Nrf2 by treating with fenofibrate improved the situation of ferroptosis, which was verified in RSL-3 induced cells. Moreover, the ferroptosis-related changes were inhibited by increasing Nrf2 in fenofibrate treated diabetic mice, which delayed the progression of DN. Collectively, we demonstrated that ferroptosis was involved in the development of DN, and up-regulating Nrf2 by treating with fenofibrate inhibited diabetes-related ferroptosis, delaying the progression of DN. Our research revealed the development mechanism of DN from a new perspective, and provide a new approach delaying the progression of DN. In diabetes, hyperglycemia causes the overload of redox-active (ferrous) iron and the accumulation of multiple sources of ROS, which provides conditions for the occurrence of ferroptosis. Simultaneously, the decreased glutathione (GSH) and glutathione peroxidase 4 (GPX4) weakened the resistance to oxidative stress, promoted the occurrence of lipid peroxidation, and ultimately led to cell ferroptosis. However, up-regulating Nrf2 by treating with fenofibrate could regulate the expression of GPX4, solute carrier family 7 member (SLC7A11), ferritin heavy chain 1 (FTH-1) and transferrin receptor 1 (TFR-1), which restored the antioxidant ability and rescued disordered iron pool, thereby inhibiting the diabetes-related ferroptosis. Image 1 • The biomarkers of ferroptosis were significantly changed in diabetic models. • Inhibition of ferroptosis alleviated the renal pathological damages in diabetic mice. • Up-regulating Nrf2 alleviated the diabetes related ferroptosis in kidneys. • Ferroptosis was involved in the progression of diabetic nephropathy. [ABSTRACT FROM AUTHOR]

• Employment accessibility is measured by considering job proximity, competition, and matching. • It is studied in a multi-modal transportation system. • The effects of poverty status, educational, and transportation mode are examined. • It finds that auto ownership is important not only for auto drivers, but also for transit riders. Accessibility has often been seen as a key indicator to assess socio-economic interactions and planning policies involving urban transportation and land use. Job competition and matching are important factors for individual job seekers as they evaluate job prospects, often including employment accessibility. However, due to inadequate data and the complex representation and interpretation of methods used, many studies have not considered job competition and matching as they attempted to assess employment accessibility. Most of the available studies do not analyze the effects of economic status, educational background, and transportation mode. In the small number of studies addressing job competition, few have considered the combination of multi-modal transportation access for commuters, though these are available in large metropolitan areas. In order to gain a better understanding of employment accessibility, this study adopts a method to assess employment accessibility by incorporating job proximity, job competition, and job matching in a multi-modal transportation system. This study focuses on the eight-county Greater Houston metropolitan region. Unemployed workers in the civilian labor force are a proxy for the number of job seekers. It is used to calculate employment accessibilities for job seekers in poverty, with different educational backgrounds, and commuting via multiple transportation modes. An interesting finding is that household auto ownership is an important determinant not only for auto drivers, but also for transit riders engaged in job seeking. In an automobile-oriented city such as Houston, driving to bus stops or rail transit stations provides job seekers significant advantages over walk-to-transit riders, especially for those living in suburban areas outside the boundary of the existing transit systems serving the central city or the core county. [ABSTRACT FROM AUTHOR]

Nitrogen availability is a key factor that regulates soil priming (the strong short-term changes in microbial decomposition of soil organic carbon after addition of fresh carbon resources); however, how soil priming changes under nitrogen addition is unclear. In this study, we collected soils from a grassland with 11-year history of nitrogen addition (0, 60, 120, and 240 kg N ha−1 yr−1 NH 4 NO 3), and the soils were incubated for 6 weeks to estimate the direction and magnitude of soil priming and the underlying microbial carbon use strategy. We found glucose addition triggered a positive priming effect among all the treatments; however, the magnitude of the positive priming did not change under nitrogen addition. The stable soil organic carbon content under different nitrogen addition levels might support the no significant change in the magnitude of those positive priming. Using DNA stable-isotope probing (DNA-SIP), we found that bacterial and fungal taxa consuming the added glucose were different in different nitrogen addition levels. The relative abundance of the K-strategist Acidobacteria increased with increasing nitrogen addition levels, while the r-strategist Firmicutes decreased with increasing nitrogen addition levels. Our results indicated microbial taxa exhibited carbon use plasticity, with most taxa altering their use of glucose under nitrogen addition. Unlabelled Image • Long-term nitrogen addition changed the quality rather than quantity of soil carbon. • Long-term nitrogen addition didn't change the magnitude of positive soil priming. • Bacterial and fungal taxa exhibited carbon use plasticity under different nitrogen addition levels. [ABSTRACT FROM AUTHOR]

Nitrogen (N) deposition is considered to be an important source of atmospheric N 2 O emission. Although N deposition simulated experiments have been conducted in grassland, forest and arctic tundra, the effect of long-term N deposition on N 2 O emission is not well understood in alpine grassland. To assess the response, a 9-yr N addition experiment was conducted in an alpine grassland of the Tianshan Mountains of Central Asia, to characterize the relationship between N 2 O emission and N application rate. An N addition rate of 10 kg N ha−1 yr−1 had no significant effect on N 2 O, while increases in N 2 O emission were clearly observed with N deposition of up to 30 kg N ha−1 yr−1 with a low emission factor (EF). The average N 2 O emission factor was 0.19% (range: 0.03%–0.42%), lower than the current IPCC default value of 1%. Nitrogen application significantly increased soil accumulated N 2 O emission throughout the growing season from 2013 to 2017, showing an increasing tendency in N 2 O emission with time. Depending on the amount and duration of N application, the interannual variability was 48.55%, 27.56%, 15.12% and 10.16% at the control (no N addition), 10, 30, 90 kg N ha−1 yr−1 plots, respectively. These would help to refine the accuracy of N 2 O mitigation protocols with insignificant N 2 O promotion under double present N deposition scenarios in alpine grassland. • N 2 O emissions increased quickly with N input ≥30 kg N ha−1 yr−1. • The longer N was added and the larger N addition effects on N 2 O emission appeared. • The current IPCC EF should be re-estimated for non N-saturation alpine grasslands. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atmospheric pesticides were characterized by a year-long 10-site sampling campaign. • Higher concentrations of atmospheric pesticides were observed in spring and summer. • Atmospheric pesticide residues are strongly influenced by cropping systems. • The risk of pesticide inhalation exposure to residents and wildlife is negligible. The intensive use of pesticides in the North China Plain (NCP) has resulted in widespread contamination of pesticides in the local atmosphere, posing risks to air quality and human health. However, the occurrence and distribution of atmospheric pesticides in the NCP as well as their risk assessment have not been well investigated. In this study, 300 monthly samples were collected using passive air samplers with polyurethane foam at ten rural sites with different crop systems in Quzhou county, the NCP, from June 2021 to May 2022. The pesticides were quantified using mass-spectrometric techniques. Our results revealed that chlorpyrifos, carbendazim, and atrazine were the most frequently found pesticides in the air samples, with detection frequencies of ≥ 87 % across the samples. The average concentrations of atmospheric pesticides during spring (7.47 pg m−3) and summer (16.05 pg m−3) were significantly higher than those during autumn (2.04 pg m−3) and winter (1.71 pg m−3), attributable to the intensified application of pesticides during the warmer seasons. Additionally, cash crop sites exhibited higher concentrations (10.26 pg m−3) of atmospheric pesticides compared to grain crop (5.59 pg m−3) and greenhouse sites (3.81 pg m−3), primarily due to more frequent pesticides spraying events in cash crop fields. These findings indicate a distinct spatial–temporal distribution pattern of atmospheric pesticides influenced by both seasons and crop systems. Furthermore, the model-based inhalation risk assessment indicates that inhalation exposure to atmospheric pesticides is unlikely to pose a significant public concern. [ABSTRACT FROM AUTHOR]

Active films based on chitosan incorporated Herba Lophatheri extract (HLE) with different concentrations were developed. Physicochemical properties of the chitosan films incorporated HLE, including density, opacity, moisture content, color, water solubility, swelling, water vapor permeability and oil resistance were measured. Biological activities of the films include antioxidant activity and antimicrobial properties, which were characterized in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and Oxford cup method, respectively. The potential interactions between chitosan and HLE in the films were investigated by Attenuated total reflectance-Fourier transform infrared analysis and X-ray diffraction. The results indicated that the moisture content, water solubility, swelling degree, water vapor permeability and oil absorption rate of chitosan/HLE films decreased up to 14.81%, 38.97%, 48.03%, 69.23% and 80% in comparison with the control chitosan film. The DPPH free radical scavenging activity of chitosan/HLE films increased by nearly 3.5 folds, and the diameter of inhibitory zone of the chitosan/HLE films extract solution against Staphylococcus aureus and Escherichia coli increased 17.02% and 19.28%, respectively. Additionally, the incorporation of HLE caused interactions between chitosan and HLE and gave rise to the chitosan/HLE films more opacity, darker, redness and yellowness appearance. In summary, the addition of HLE enhanced the moisture and oil resistance, antioxidant activity which declined with time, and antimicrobial activity of the chitosan film, which were all desirable for food packaging. • Herba Lophatheri extract (HLE) was incorporated into the chitosan film. • The effects of HLE on properties of the chitosan film were investigated. •The addition of HLE caused changes in opacity and color of the chitosan film. • Chitosan/HLE films showed better moisture and oil resistance, antioxidant and antimicrobial activities. [ABSTRACT FROM AUTHOR]

• Three crop rotations were studied in Chongqing over five years. • Reduced fertilizer promoted grain yields and environmental and economic benefit. • The rice-wheat rotation produced the highest grain yield and economic benefit. • The maize-wheat rotation was not suitable for Chongqing. • The rice-flooded fallow rotation is the most suitable system for Chongqing. A suitable crop rotation with optimum fertilizer application can balance the need for high crop yields with minimal environmental risk. This has not yet been achieved in China, and the Chinese Government now requires rotations that include a fallow period with the aim of improving soil quality. As a step towards achieving these aims, a 5-year field experiment was carried out to evaluate the effects of different rates of nitrogen (N) fertilizer in three typical and acceptable crop rotations on grain yield, nitrogen use efficiency (NUE), N balance and economic benefit at Jiangjin, Chongqing, China. The rotations were rice-flooded fallow (RF), rice-wheat (RW) and maize-wheat (MW). Three fertilizer treatments were tested over five years. The RW rotation with reduced fertilizer application had the highest grain yield and generated the highest economic benefit. The MW rotation was not suitable for the region that we studied because high precipitation can cause serious disease problems for the wheat. The RF rotation with reduced fertilizer application proved to be the best system for ensuring food security, increasing economic benefit and reducing environmental risk. [ABSTRACT FROM AUTHOR]

Meningioma subtypes are one of the most common key points to the treatment and prognosis of patients. The purpose of this study was to investigate the differential diagnostic value of radiomics features on meningioma. A total of 241 patients with meningioma who had undergone tumor resection were randomly selected including 80 with meningothelial meningioma, 80 with fibrous meningioma, and 81 with transitional meningioma. These meningiomas were divided into 4 groups including: meningothelial versus fibrous (group 1), fibrous versus transitional (group 2), meningothelial versus transitional (group 3), and meningothelial versus fibrous versus transitional (group 4). All patients were examined using the same magnetic resonance scanner (GE 3.0 T) and the preoperative contrast-enhanced T1-weighted images were available. Radiomics features from the contrast-enhanced T1-weighted images of 241 patients were evaluated by 2 experienced radiology specialists. A total of 385 radiomics features were extracted from the images of each patient. Several preprocessing methods were applied on the radiomics dataset to reduce the redundancy and highlight differences between different meningioma before the Fisher discrimination analysis was adopted and leave one out cross validation methods were used for the model validation. The differentiation accuracies of the Fisher discriminant analysis model for groups 1, 2, 3, and 4 were 99.4%, 98.8%, 100% and 100%, respectively; leave one out cross validation method was achieved for group 1, 2, 3, and 4 with the accuracies of 91.3%, 95.0%, 100%, and 94.2%, respectively. Radiomics features and the combined Fisher discriminant analysis could provide satisfactory performance in the preoperative differential diagnosis of meningioma subtypes and enable the potential ability for clinical application. [ABSTRACT FROM AUTHOR]

Abstract An effective parallelization algorithm based on the compute-unified-device-architecture (CUDA) is developed for DEM generalization that is critical to multi-scale terrain analysis. It aims to efficiently retrieve the critical points for generating coarser-resolution DEMs which maximally maintain the significant terrain features. CUDA is embedded into a multi-point algorithm to provide a parallel-multi-point algorithm for enhancing its computing efficiency. The outcomes are compared with the ANUDEM, compound and maximum z-tolerance methods and the results demonstrate the proposed algorithm reduces response time by up to 96% compared to other methods. As to RMSE, it performs better than ANUDEM and needs half the number of points to keep the same RMSE. The mean slope and surface roughness are reduced by less than 1% in the tested cases. The parallel algorithm provides better streamline matching. Given its high computing efficiency, the proposed algorithm can retrieve more critical points to meet the demands of higher precision. Highlights • We present a parallelization method for DEM generalization based on CUDA. • We propose a parallel-multi-point algorithm to extract the critical points from the DEM. • The method reduces response time by up to 96% compared with three existing methods. • The method can better sustain the drainage features during the generalization process than three existing methods. [ABSTRACT FROM AUTHOR]

Abstract There has been increasing interest in and use of biochar as a soil amendment. However, the effects of biochar addition on ammonia volatilization (AV) appeared contradictory from the many reported studies and the main influencing factors remain unclear. Here, we conducted a comprehensive meta-analysis of 41 published articles with 144 observations to reveal the effects of biochar addition on AV and used a boosted regression tree modelling approach to further interpret the contribution of biochar characteristics, soil properties and experimental conditions to this process. On average, biochar addition did not impact on AV, but this varied greatly under different soil, biochar and experimental conditions. The pH of soil and biochar were important factors impacting AV. Biochar application to acidic soil could stimulate AV, and addition of biochar with a high pH and at a low application rate also showed the same trend. In contrast, combining biochar with urea or organic fertilizer, or using wood-based or acidified biochar at appropriate rates had benefits in reducing AV. These findings have major implications for biochar management strategies in agricultural systems, where an important consideration is the mitigation of potentially detrimental environmental consequences. Graphical abstract Unlabelled Image Highlights • The pH of soil and biochar were crucial factors impacting ammonia volatilization. • Biochar applied in acidic soil could stimulate ammonia volatilization. • Adding acidic biochar had benefit for reducing ammonia volatilization. • Combining biochar with organic fertilizer could decrease ammonia volatilization. [ABSTRACT FROM AUTHOR]