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Hydrogen generation is the initial challenge in utilization of hydrogen energy. In this work, robust hydrogen generation with a high yield of 53,930 μmol g−1 is demonstrated over layered crystalline silicon material derived from topochemical reaction from CaSi2. The physicochemical properties of the resultant layered crystalline Si material before and after H2 generation are investigated in detail to illustrate the H2 generation mechanism. Integrated H2 evolution routes, including destruction of Si–H bonds, oxidation of Si–Si bonds (hydrolysis of Si) and photocatalytic splitting water, are revealed to be responsible for the robust H2 generation. This work delivers a facile route to synthesize layered crystalline Si material with promising H2 generation performance and gives a deeply insight into the H2 evolution mechanisms of Si-based materials.

Vacancies engineering was widely reported as the promising strategy for the improvement of the photocatalytic performance of semiconductor photocatalysts. In current work, carbon vacancies are constructed successfully in graphitic carbon nitride (g-C3N4) photocatalyst via magnesium vapor etching. Experimental results show that the formed carbon vacancies in g-C3N4 photocatalyst can significantly improve the photocatalytic H2 generation performance. XRD, FTIR, SEM/TEM, XPS and PL characterization data are employed to evidence the construction of carbon vacancies, which are revealed to be the reason for the enhancement of photocatalytic H2 evolution. This work develops an alternative route to construct carbon vacancies in g-C3N4 materials and gives an insight into the influence of vacancies on the photocatalytic performance of photocatalysts.

Myocardial fibrosis leads to cardiac remodeling and dysfunction. Curcumae Rhizoma has been utilized in clinical trials to treat a variety of cardiovascular illnesses, although its role in myocardial fibrosis is unknown.The purpose of current study was to explore the potential mechanism action and anti-myocardial fibrosis effects of treatment with Curcumae Rhizoma.The chemical components in the aqueous extract from Curcumae Rhizoma were identified using GC-MS analysis. A prediction network describing the relationship between Curcumae Rhizoma and MF was established based on information collected from multiple databases. Functional enrichment analysis was performed to investigate the specific functions and pathways involved in the candidate Curcumae Rhizoma targets acting on MF, which were further validated by vivo experiments.There were 444 targets obtained from the 39 active ingredients in Curcumae Rhizoma, and 5691 disease targets related to MF were identified. Then, 41 key targets were determined with the PPI interaction network, which was structured from 324 overlapping gene targets. GO and KEGG analyses revealed that the p38 MAPK/NF-κB and TGF-β1/Smad2/3 signaling pathways might play crucial roles in the therapeutic mechanism of MF. According to the results of molecular docking, the binding activity between core components and targets was marvelous (affinity -6 kcal/mol). Take it a step further, the experimental validation data affirmed that Curcumae Rhizoma substantially decreased myocardial fibrosis and recovered cardiac function in the ISO-induced rats. The associated proteins expression data implied that the p38 MAPK/NF-κB and TGF-β1/Smad2/3 pathways might be vital in the anti-fibrosis effect of Curcumae Rhizoma.The findings suggested that Curcumae Rhizoma diminished myocardial fibrosis by suppressing fibrosis multiplication and collagen deposition through inhibiting p38 MAPK/NF-κB and TGF-β1/Smad2/3 pathways, which might be a promising therapeutic medicament for alleviating myocardial fibrosis.

The metabolism and utilization of nitrogen (N) in dairy cows can be affected by phosphorus (P), as insufficient P intakes reduce ruminal fermentation, resulting in low microbial protein production and nutrient digestibilities. There has been renewed research in recent years on the requirements of N and P of dairy cows in an effort to reduce their excretion, but most studies were conducted with a nutrient fixed while evaluating the level of the other nutrient in the diet. This experiment was undertaken to study the effect of reducing both dietary N and P on excretion and production of dairy cows. Eight lactating cows were paired in a replicated 4 × 4 Latin square design with 20-d periods, and cows in each pair were randomly assigned to one of the following four dietary treatments: low crude protein (CP), low P (15% CP, 0.34% P), low CP, medium P (15% CP, 0.39% P), low CP, high P (15% CP, 0.44% P), and high CP, high P (17% CP, 0.44% P). Reducing dietary protein from 17 to 15% resulted in increased conversion of intake N to milk N (P = 0.05) and reduced milk urea N (P

Urban expansion is a crucial process altering nutrient cycles in agro-ecosystems, often accompanied by negative impacts on the environment. Quantitative analysis of nutrient flows in agricultural systems of megacities and their interactions with urbanization is still lacking. This study reports on changing patterns in inputs, outputs, losses and cycling of nitrogen (N) and phosphorus (P) in agricultural systems in three of China’s megacities–Beijing, Shanghai and Chongqing during 1990–2014, using the substance flow analysis method. Results show that changing patterns of nutrient flows varied among cities. With rising urbanization rate in Chongqing, nutrients were increasingly imported to agricultural systems to sustain food demand, which led to increased nutrient losses. An opposite trend occurred in Beijing and Shanghai with high urbanization levels (over 80%) since the early 2000s, resulting from a decline in cropland and livestock numbers, and stricter enforcement of environmental laws. Mineral fertilizers and livestock husbandry both contributed largely to ammonia emissions from agriculture. Losses of nutrients to water bodies in Beijing were sourced mainly from the livestock sector, while derived from overuse of mineral fertilizers in Chongqing, suggesting that priority management practices need to be designed differently among regions. Increased intensity of nutrient losses from agriculture was significantly correlated with increased mineral fertilizer input, livestock density and feed import and with reduced recycling ratio of manure. Integrated management for better use of nutrients in fertilizers, feed and manure are urgently required at regional scales. Our findings can serve as basis for policy decisions for sustainable agricultural systems in megacities.

MicroRNAs (miRNAs) contribute to tumorigenesis and progression via acting as tumor suppressors or oncogenes in human cancer. Aberrant expression of miR-302c has been reported in various types of cancer except colorectal cancer (CRC). Thus, our study was aimed to verify the expression of miR-302c and its functional role in CRC. We found a significant reduced expression of miR-302c in CRC tissues compared to tumor-adjacent tissues. Low miR-302c level was remarkably correlated with deeper tumor invasion, lymph node metastasis and advanced TNM stage. Importantly, low miR-302c expression was identified as an independent indicator for poor prognosis of CRC patients. Overexpression of miR-302c repressed migration and invasion capacities of SW620 and SW480 cells in vitro. Mechanistically, miR-302c inversely regulated transcription factor AP4 (TFAP4) abundance in both SW620 and SW480 cells, and it negatively correlated with TFAP4 mRNA expression in CRC samples. Herein, TFAP4, a regulator of epithelial-mesenchymal transition (EMT), was recognized as a direct target gene of miR-302c in CRC. Otherwise, miR-302c overexpression increased E-cadherin expression and reduced the levels of Vimentin and SNAI1, suggesting an inhibitory effect of miR-302c on EMT of CRC cells. Notably, our findings established that the EMT and metastasis of Caco-2 cells were enhanced by miR-302c knockdown, and subsequently reversed by TFAP4 silencing. Collectively, these data indicate that miR-302c represses EMT and CRC metastasis possibly by targeting TFAP4, and it may serve as a potential prognostic factor and therapeutic target for CRC.

Pothole is one of the most serious distresses of steel bridge deck pavement. Rapid and durable patching material is required for pothole treatment to reduce the maintenance influence on transportation service. In this paper, a cold-mixed patching material was developed on the basis of a fast cured thermosetting binder. The optimal binder formula was determined by optimization and balancing of mechanical property, workability and strength development, through tensile tests, viscosity tests and differential scanning calorimetry tests. After that, the high temperature performance, low temperature performance, moisture susceptibility and fatigue performance of the newly developed material were evaluated through a laboratory experimental program, including wheel track test, 3-point bending beam test, indirect tensile test and fatigue test. On the other hand, a numerical simulation was conducted to assess the structural performance of the material when using on the steel bridge deck. The result showed that the developed binder material had tensile strength over 2MPa and elongation over 100%. The workable time was over 30 min and the favorable compaction time was 36 min after mixing at 25 °C. The patching material had a rapid traffic reopen capability in three hours. In addition, the developed material had rather good mechanical and structural performance when used in pothole patching on steel bridge deck pavement.

Agriculture affects climate change and contributes directly and indirectly to greenhouse gas (GHG) emissions. However, no reports have fully quantified the GHG emissions from different crop systems in China. In this study, the carbon emission and carbon sequestration inventories and the carbon footprint (CF) of 16 major crop systems in China from 2001 to 2018 were analyzed with a cradle-to-farm gate life cycle analysis approach for the first time. The results showed that the largest farm CF and product CF were vegetables (11.9 t CO2 eq ha−1) and tea (4.6 t CO2 eq t−1), respectively. From the perspective of crop emissions and processes, the main crop systems influencing the national total net carbon emissions (NTCE) from crop production are rice, maize, wheat, fruits and vegetables, accounting for 87.3–90.4%; the key emission processes for NTCE are fertilization and irrigation, accounting for 73.7–76.8%. The NTCE has increased by 410.4 Mt CO2 eq from 2001 to 2018, of which maize, fruits and vegetables were the main crops that explained 99.0%, while fertilization and irrigation were the key factors and explained 91.9% of these increases. Scenario analysis indicated that increasing the straw return rate and partially replacing chemical fertilizers with manure have a minimal impact on NTCE. In contrast, reducing the loss of reactive nitrogen is the most effective single strategy to alleviate agricultural GHG emissions in the future. Our results will provide a fresh perspective for the development of more effective GHG emission reduction strategies for agricultural green development.

It is necessary to obtain accurate ammonia (NH3) emission estimates from concentrated cattle operations to evaluate the contribution of emissions from dairy and beef feedlots in the Beijing-Tianjin-Hebei (or the “Jing-Jin-Ji”) district of China to local dust-haze pollution such as fine particulate matter (PM2.5) and the national animal NH3 inventory. This study examines NH3 emission rates from two dairy and two beef feedlots in four different seasons, which were measured using an inverse dispersion technique in combination with an open-path tunable diode laser. Ammonia emissions from both dairy and beef feedlots are characterized by a distinctive diel pattern with high emission rates during the middle of the day and low rates during the night, which is in good agreement with the diel variation in air temperature and wind speed. In addition, apparent seasonal difference in NH3 emissions from dairy and beef feedlots were also observed, where the greatest emission occurred in summer followed by spring/fall and winter. Annual emission factors (EFs) for beef and dairy feedlots in the Jing-Jin-Ji district were estimated to be approximately 19.8 kg NH3 head−1 yr−1 and 47.8 kg NH3 head−1 yr−1, respectively, accounting for 25% and 30% of the feed N inputs. The NH3 emissions from beef and dairy cattle in this district were estimated to be 45.73 and 105.52 kt, respectively. In future, more field measurements on animal feedlots with various feed/manure management practices, stocking densities and weather conditions are highly requested to reduce NH3 emission uncertainty and characterize the N cycling within animal feedlots.

Agriculture in China has been smallholder based. Tempted by a large food demand, smallholders have been using excessive fertilizer to obtain high yields. This type of production has impaired the country's food production and environmental sustainability. There are, however, some innovative smallholders who are more adaptive to new technologies, have become more successful in production and nutrient utilization. In this study, we analysed the outlook of transforming smallholder agriculture in China into sustainable food production. First, we collected a database from a survey of 6.6 million smallholders engaged in the production of a total of 54 crops, which were categorized into cereals, fruits, vegetables, and others. From the database we assessed the extent of nitrogen (N) overuse by counties. Then we identified the top 10% performers in crop yield and N efficiency as prime producers. These prime producers were 15.3–35.4% higher in crop yield but 16.0–21.0% lower in N fertilizer use than their cohorts, and consequently 17.2–37.6% higher in economic returns. Replicating the success of the prime producers in agriculture in China would enable the country to reduce N use by 32.9% and land use by 11% without changing production. In the meantime, nitrate leaching from cropland would be brought down below the threshold for water safety. Based on the data we developed a model for transforming smallholder agriculture to sustainable food production through co-operation with stakeholders. This model could be used as a reference for producers, investors, and policy makers.

Inappropriate management of pig manure contributes considerably to pollution of waterbodies by nitrogen (N) and phosphorus (P), and to air pollution by ammonia (NH3) and hydrogen sulfide (H2S) emissions. Dietary manipulation is recognized as a possible pollution mitigation measure, but it may affect pig growth and thereby production costs. Here we present a global meta-analysis of the effects of dietary manipulation on nutrient (N and P) excretion, gaseous (NH3 and H2S) emissions from manure, and growth performance of pigs, using data from 245 published studies. Four groups of dietary manipulation were distinguished, namely i) lowering dietary crude protein (CP) content, (ii) supplementing exogenous enzymes, (iii) supplementing fermented feed ingredients, and (iv) supplementing other additives (e.g. fermentable carbohydrates, acidifying agent/salts and probiotics) in feed. In addition, the cost-effectiveness of dietary manipulations was evaluated, expressed as US $ per kg N excretion abated. Results show that lowering CP content significantly reduced both total N excretion (28.5%) and NH3 emissions (34.4%). Addition of protease reduced N excretion (18.2%) but did not affect NH3 emissions. Supplementing other additives simultaneously reduced NH3 emissions (21.5%) and H2S emissions (23.2%). Adding phytase to feed significantly decreased total P excretion by 31.4%. Diets with fermented feed ingredients tended to decrease N excretion and emissions, but this effect was not statistically significant. All dietary manipulations significantly improved the growth performance regarding the weight gain and feed efficiency, except for lowering CP content. But lowering dietary CP content within a moderate level in combination with adding additional amino acids did not impair pig growth. The cost-effectiveness analysis indicated that various diary manipulation measures were economically beneficial to farmers through improved feed-to-meat conversion efficiency. Our results can support to the design of proper dietary formulations so as to simultaneously reduce N and P excretion and associated emissions, meanwhile enhance the growth performance of pigs with lower economic cost.

Prior research has focused on designing training approaches for novice operators to support maximum motor skill development. However, in production operations, workers must be trained to uniform performance levels to prevent ‘bottlenecks’ or work-in-process inventory accumulation. This study introduces a new approach to support assignment of training protocols to operators to achieve comparable levels of motor performance. Thirty-six participants performed a computer-based motor test. Based on performance classification results, each participant was assigned to a specific haptic virtual reality training condition. Results revealed participants identified as ‘medium’ or ‘low’ performers achieved levels of motor performance comparable to ‘high’ performers through 1-h training. Relevance to Industry Findings can be applied to operator training in manual assembly operations, promoting a group of novice workers to achieve uniform performance levels and mitigating production bottlenecks.

Large-scale animal production plants and specialized cash crop production systems have developed in China in recent decades. In the Beijing region this has led to livestock densities of nearly 11 livestock units (LU) per hectare, resulting in over-fertilization of soils and pollution of the aquatic and atmospheric environments. A soil screening investigation including five main cropping systems was carried out in the Shunyi and Huairou Districts of Beijing from 2009 to 2011. Soils (calcaric Eutric Cambisols) were sampled on 26 farmers’ field plots to a depth of 200 cm and analysed for soil organic carbon (SOC), hot water-soluble carbon (Chws), total and plant-available macronutrients, pH (H2O) and CaCO3. Fertilization practice was obtained via farmers’ interviews. The status of major potential pollutants in animal husbandry (veterinary antibiotics and growth-promoting heavy metals and arsenic) reaching the field plots via manure application was investigated. Most of the investigated soils were over-supplied with nutrients. High amounts of farmyard manure (FYM) averaging 45 ± 69 t DM ha−1 y−1 were applied to most of the observed field plots in 2008, with mean total pure nutrient amounts of 967 ± 1297 kg nitrogen (N), 379 ± 535 kg phosphorus (P) and 751 ± 889 kg potassium (K) ha−1 y−1 (n = 19). Additional nutrient applications with mineral fertilizers amounted to 276 ± 122 kg N, 37 ± 62 kg P and 21 ± 26 kg K ha−1 y−1 (n = 16). Comparing current (2009) soil nutrient contents in 0–20 cm with data from the Second Chinese National Soil Survey of 1981, significant increases in SOC (from 0.71% to 0.95%), total N (from 0.08% to 0.13%) and available P (from 7.3 mg kg−1 to 60 mg kg−1) were observed. Sulfonamide antibiotics were found in topsoils and subsoils, whereas tetracyclines and fluoroquinolones mainly remained in the topsoil. The “natural background value” for Cu and Zn, based on the Chinese environmental quality standard was exceeded in topsoil samples on four and three sites, respectively. Crop-specific fertilizer recommendations were derived and options for different manure processing and transport technologies are discussed. An evaluation of the risks associated with veterinary antibiotics, heavy metals and arsenic is given.

Two novel mitogenomes of Eozapus setchuanus (KJ648495) and Sicista concolor (KJ648496) were reported and their total lengths were 16,630 bp and 16,493 bp, respectively. Both mitogenomes which were analogous to other rodent mitogenomes, contained 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a control region. Specifically, the ND2 gene of S. concolor has three amino acids lesser than that of two other Dipodidae species (E. setchuanus and Jaculus jaculus) due to a premature termination codon in the 3′ end. We detected a tandem repeat cluster of 221 bp and 274 bp in the control region of S. concolor and E. setchuanus, respectively. Along with phylogenetic relationship analysis, we speculated that the tandem repeats in control regions might be common in Dipodinae species. Our phylogenetic analysis using concatenated mitochondrial gene datasets suggested five suborder and 16 family monophyletic groups in 54 rodent taxa sampled and strongly supported a basal position of the squirrel-related clade (PP = 1; BP = 100). Dipodidae had a sister-group relationship with Muroidea, and Sicistinae was in the base of Dipodidae clade. The complete mitochondrial genomes showed high resolution in deep-level phylogenetic relationship reconstructions of Rodentia.

Accurately quantifying methane (CH4) and nitrous oxide (N2O) emissions from beef operations in China is necessary to evaluate the contribution of beef cattle to greenhouse gas budgets at the national and global level. Methane and N2O emissions from two intensive beef feedlots in the North China Plain, one with a restricted feeding strategy and high manure collection frequency and the other with an ad libitum feeding strategy and low manure collection frequency, were quantified in the fall and spring seasons using an inverse dispersion technique. The diel pattern of CH4 from the beef feedlot with an ad libitum feed strategy (single peak during a day) differed from that under a restricted feeding condition (multiple peaks during a day), but little difference in the diel pattern of N2O emissions between two feeding strategies was observed. The two-season average CH4 emission rates of the two intensive feedlots were 230 and 198 g CH4 animal−1 d−1 and accounted for 6.7% and 6.8% of the gross energy intake, respectively, indicating little impact of the feeding strategy and manure collection frequency on the CH4 conversion factor at the feedlot level. However, the average N2O emission rates (21.2 g N2O animal−1 d−1) and conversion factor (8.5%) of the feedlot with low manure collection frequency were approximately 131% and 174% greater, respectively, than the feedlot under high frequency conditions, which had a N2O emission rate and conversion factor of 9.2 g N2O animal−1 d−1 and 3.1%, respectively, indicating that increasing manure collection frequency played an important role in reducing N2O emissions from beef feedlots. In addition, comparison indicated that China’s beef and dairy cattle in feedlots appeared to have similar CH4 conversion factors.

White-on-blue logo signs on the sides of highways are typically used to notify drivers of food, gas, and lodging at an upcoming interchange. The current research assessed driver performance and attention allocation in a simulated freeway driving task when exposed to six-panel logo signs, nine-panel logo signs, mileage guide signs, and roadway work zones both with and without an in-car navigation device. The objective was to identify the impact of signage types on driver behavior under realistic driving conditions. Results revealed glance durations and fixation frequencies to guide signs to be significantly lower than with six-panel and nine-panel logo signs, but no differences were found between six-panel and nine-panel logo signs. There were also statistical differences among the independent variables for speed deviation and lane deviation, but magnitudes were not large enough to be considered practically significant in terms of driving safety. Overall, there were minor differences in sign processing time between logo signs and mileage guide signs, but such differences did not translate to degradations in vehicle control.

Evaluation of the global warming potential of the dairy industry both in China and globally necessitates reliable characterization of CH4 and N2O emissions. However, CH4 and N2O emissions from dairy operations differ with feeds, herd structures and manure management practices, and the lack of N2O and CH4 emission measurements for China, especially for intensive dairy operations, causes substantial uncertainty in accounting for GHGs from dairy operation both in China and globally. In this study, CH4 and N2O emissions during summer to fall period from an intensive feedlot in China were characterized to fill the data gap. The diurnal CH4 emission patterns for milking cows and heifers were driven by the feeding activities and the diurnal N2O patterns by the diurnal changes in temperature. The CH4 emission rates of 397 g head−1 d−1 (23.63 L CH4 kg−1 milk) (in summer) and 279 g head−1 d−1 (in fall) for milking cows and heifers accounted for 5.17% and 7.68% of their daily gross energy intakes, whereas the N2O emission rates of 36.7 g head−1 d−1 (0.85 L N2O kg−1 milk) for milking cows and 24.2 g head−1 d−1 for heifers accounted for 4.25% and 6.86% of the daily feed N intake. The CH4 conversion factor and CH4 emission intensity in the measurement season for intensive dairy operations in China are lower than those for collective operations in China, and the CH4 emission intensity is similar to those in developed countries.

Ammonia (NH 3 ) emissions from livestock production in China are an important contributor to the global NH 3 budget. In this study, by estimating total nitrogen (N) intake based on herd structures and excreted N, a mass balance model was used to estimate NH 3 losses from animal housing and manure storage facilities of dairy cattle, beef cattle, pigs, broiler and layer productions within animal farm gate and their corresponding NH 3 emission intensities on the basis of animal products, N and protein in animal products. In 2009, NH 3 emissions from pigs, layers, beef and dairy cattle and broiler production systems in China were 1.23, 0.52, 0.24, 0.21 and 0.09 million tons, respectively. The NH 3 emission intensities were 26.6 g NH 3 –N kg −1 of pork, 28.1 g NH 3 –N kg −1 of layer eggs, 39.4 g NH 3 –N kg −1 of beef meat, 6.0 g NH 3 –N kg −1 of dairy milk and 4.6 g NH 3 –N kg −1 of chicken meat, or 1260 (pigs), 1514 (layers), 1297 (beef), 1107 (dairy) and 123 g NH 3 –N (broilers) kg −1 N in animal products. Of the sectors of NH 3 emission, manure storage facilities and farmyard manure (FYM) in animal housing were the major contributors to the total NH 3 emissions except for layers; housing emissions from slurry were also major contributors for dairy and pig production.

Increasing fertilizer phosphorus (P) application in agriculture has greatly contributed to the increase of crop yields during the last decades in China but it has also increased P flows in food production and consumption. The relationship between P use efficiency and P flow is not well quantified at national level. In present paper we report on P flows and P use efficiencies in rice, wheat, and maize production in China using the NUFER model. Conservation strategies for P utilization and the impact of these strategies on P use efficiency have been evaluated. Total amounts of P input to wheat, rice, and maize fields were 1095, 1240, and 1128 Gg, respectively, in China, approximately 80% of which was in chemical fertilizers. The accumulation of P annually in the fields of wheat, rice, and maize was 29.4, 13.6, and 21.3 kg ha(-1), respectively. Phosphorus recovered in the food products of wheat, rice, and maize accounted for only 12.5%, 13.5%, and 3.8% of the total P input, or 3.2%, 2.6%, and 0.9% of the applied fertilizer P, respectively. The present study shows that optimizing phosphorus flows and decreasing phosphorus losses in crop production and utilization through improved nutrient management must be considered as an important issue in the development of agriculture in China.

Accurately determining methane emission factors of dairy herd in China is imperative because of China’s large population of dairy cattle. An inverse dispersion technique in conjunction with open-path lasers was used to quantify methane emissions from a dairy feedlot during the fall and winter seasons in 2009–2010. The methane emissions had a significant diurnal pattern during both periods with three emission peaks corresponding to the feeding schedule. A 10% greater emission rate in the fall season was obtained most likely by the higher methane emission from manure during that period. An annual methane emission rate of 109 ± 6.7 kg CH 4 yr −1 characterized with a methane emission intensity of 32.3 ± 1.59 L CH 4 L −1 of milk and a methane conversion factor ( Y m ) of 7.3 ± 0.38% for mature cattle was obtained, indicating the high methane emission intensity and low milk productivity in Northern China.