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Abstract Nickel (Ni) nanoparticles can be enriched on the surface of iron-based frictional pairs, which provides the possibility to get rid of the competitive adsorption between the polar species of vegetable oil and the surface-active nano-additives thereon. In this paper, nickel acetylacetonate was used as a precursor to in-situ synthesize nickel nanoparticles with an average diameter of about 12 nm in rapeseed oil (RO) as the reducing agent, surface modifier, and solvent as well. The tribological properties of the as-synthesized Ni nanoparticles were evaluated with a four-ball tribometer, and their tribomechanism was investigated based on the characterizations of the tribofilm on rubbed steel surfaces by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). It was found that the Ni nanoparticles in-situ prepared in the RO with a mass fraction of 0.3% can reduce the wear scar diameter (WSD) of the steel ball by 36%. This is because, on the one hand, the Ni nanoparticles are adsorbed on the rubbed steel surfaces to repair or fill up the micro-pits and grooves thereon. On the other hand, Ni nanoparticles participate in tribochemical reactions with atmospheric O and steel substrate to form the tribochemical reaction film on the rubbed steel surfaces with the assistance of friction-induced heat and applied normal load. In addition, an amorphous carbon film is formed on the rubbed surface via the carbonization of base oil under the catalysis of Ni nanoparticles. The adsorbed Ni layer, the tribochemical reaction film, and the carbon layer comprise a composite tribofilm composed of amorphous carbon, polar fatty acid, metallic nickel, iron oxides, and nickel oxides on the rubbed steel surfaces, which contributes to significantly improving the antiwear ability and load-carrying capacity of the RO for the steel–steel sliding pair.

Abstract Organic molybdenum lubricant additive like molybdenum dialkyl dithiocarbamate (MoDTC) can cause wear acceleration of diamond-like carbon (DLC) coating coupled with steel under boundary lubrication, which hinders its industrial application. Therefore, polyisobutylene succinimide (PIBS), an organo molybdenum amide, was adopted to modify molybdenum oxide affording molybdenum polyisobutylene succinimide-molybdenum oxide nanoparticles (MPIBS-MONPs) with potential to prevent the wear acceleration of DLC coating. The thermal stability of MPIBS-MONPs was evaluated by thermogravimetric analysis. Their tribological properties as the additives in di-isooctyl sebacate (DIOS) were evaluated with MoDTC as a control; and their tribomechanism was investigated in relation to their tribochemical reactions and synergistic tribological effect with zinc dialkyldithiophosphate (ZDDP) as well as worn surface characterizations. Findings indicate that MPIBS-MONPs/ZDDP added in DIOS can significantly reduce the friction and wear of DLC coating, being much superior to MoDTC. This is because MPIBS-MONPs and ZDDP jointly take part in tribochemical reactions to form a composite tribofilm that can increase the wear resistance of DLC coating. Namely, the molybdenum amide on MPIBS-MONPs surface can react with ZDDP to form MoS2 film with excellent friction-reducing ability; and MPIBS-MONPs can release molybdenum oxide nanoparticle to form deposited lubrication layer on worn surfaces. The as-formed composite tribofilm consisting of molybdenum oxide nanocrystal, amorphous polyphosphate, and molybdenum disulfide as well as a small amount of Mo2C accounts for the increase in the wear resistance of DLC coating under boundary lubrication.

Photodynamic therapy has been a promising technique for the treatment of tumours. In this manuscript, the authors report on the photoactivation of the osmium peroxo complex and its potential use for chemotherapy and photodynamic therapy under blue light irradiation against tumours in their hypoxic environment.

Farmland transfer (FT) is the key to achieving moderate agricultural scale management in China. Clarifying the spatial pattern of FT is important to improve FT strategies. In this study, the multinomial logit model was used to reveal the spatial pattern of FT in Liaoning Province, Northeast China. On this basis, the reasons for its formation were discussed, and suggestions were proposed. According to the statistical results, 39.7% of the sample peasant households participated in FT. Most of them live far from the regional core area. Regression analysis shows that the FT in Liaoning Province has a significant “core-periphery” spatial pattern. As the spatial distance between the residence and the regional core area (SDRRC) increases, the probability of FT rises for peasant households. Specifically, the odds ratios of farmland transfer out and farmland transfer in rise by 0.9% and 0.6% on average, respectively, for each 1 km increase in SDRRC. Widespread concurrent business and the increase in FT fees due to imperfect urbanization are the main reasons for the formation of the spatial pattern. We suggest that the promotion of FT requires high-quality urbanization in central cities, accelerating urbanization in medium and small cities and counties, implementing differentiated FT subsidy standards, and promoting new agricultural scale management models.

Sonodynamic therapy has therapeutic promise due to its safety and good tissue penetration, but is currently bottlenecked due to a lack of efficient and safe sonosensitizers. Here the authors show that [Ru(bpy)3]2+ can produce singlet oxygen and sonooxidize NADH in deep tissue, and destroy mouse tumors effectively.

Camptothecin is a monoterpene indole alkaloid with anti-tumor activity. Here, the authors assemble the genome of the camptothecin producing plant Camptotheca acuminata and provide insights into the evolutionary origin of camptothecin biosynthesis by comparing to the vinblastine and vincristine biosynthetic pathway in Catharanthus roseus.

Biosynthetic pathway of chicoric acid in purple coneflower has not been fully elucidated, though the compound has been shown to have potential health benefits. Here, the authors report the involvement of both BAHD and SCPL acyltransferases in its biosynthesis and show the pathway is unique to Echinacea species.

Abstract In this study, water soluble CuO nanostructures having nanobelt, nanorod, or spindle morphologies were synthesized using aqueous solutions of Cu(NO3)2·3H2O and NaOH by adjusting the type of surface modifier and reaction temperature. The effect of morphologies of these various CuO nanostructures as water-based lubricant additives on tribological properties was evaluated on a UMT-2 micro-friction tester, and the mechanisms underlying these properties are discussed. The three different morphologies of CuO nanostructures exhibited excellent friction-reducing and anti-wear properties. Tribological mechanisms differed in the initial stage of frictional interactions, but in the stable stage, a tribochemical reaction film and adsorbed lubricious film on the rubbing surfaces played important roles in hindering direct contact between friction pairs, leading to improved tribological properties.

Nanoparticles as lubricant additives demonstrate powerful friction reduction and antiwear properties and are potential alternatives to traditional additives in line with green and environmentally friendly requirements. However, the vast majority of currently available research focuses on the tribological properties of various nanoparticles in base oils at laboratory, which has a large gap with their application in engineering. To cope with the rapid economic and industrial development in China, there is a need to improve the tribological properties of nanoparticles. This paper highlights the current status and development trend of nanoparticles as lubricant additives in China. The factors influencing the tribological properties of nanoparticles, such as their composition, particle size and morphology, as well as the base stocks and their combination with other additives, are summarized. Furthermore, the research progress in the lubrication mechanism of nanoparticles is discussed, and the issues concerning the application of nanoparticles as lubricant additives as well as their future directions are discussed. This review is expected to provide an impetus to guide the design of high-performance, fully formulated lubricant systems containing nanoparticles as the lubricant additive.

This study presents a GIS-based method integrating hourly transport pathways and wind-field grid reconstruction, straw open burning (SOB) source identification, and a two-stage spatiotemporal multi-box modeling approach to quantify the contribution of external sources of SOB to elevated urban PM2.5 concentrations during a specific pollution episode (PE) at a high temporal resolution of 1 h. Taking Jilin Province as an empirical study, the contribution of SOB in province-wide farmlands to urban haze episodes in Changchun during the SOB season of 2020–2021 was evaluated quantitatively using a combination of multi-source datasets. The results showed that Changchun experienced three severe PEs and one heavy PE during the study period, and the total PM2.5 contributions from SOB sources were 352 μg m−3, 872 μg m−3, and 1224 μg m−3 during the three severe PEs, respectively; these accounted for 7%, 27%, and 23% of the urban cumulative PM2.5 levels, which were more obvious than the contribution during the PE. The total PM2.5 contribution from SOB sources (4.9 μg m−3) was only 0.31% of the urban cumulative PM2.5 level during the heavy PE. According to the analysis of the impact of individual factors, some policy suggestions are put forward for refined SOB management, including control spatial scope, burning time interval, as well as burning area limit under different urban and transport pathways’ meteorological conditions and different transport distances.

Abstract A magnetic ionic liquid (abridged as MIL) [C6mim]5[Dy(SCN)8] was prepared and used as the magnetic lubricant of a steel-steel sliding pair. The tribological properties of the as-prepared MIL were evaluated with a commercially obtained magnetic fluid lubricant (abridged as MF; the mixture of dioctyl sebacate and Fe3O4, denoted as DIOS-Fe3O4) as a control. The lubrication mechanisms of the two types of magnetic lubricants were discussed in relation to worn surface analyses by SEM-EDS, XPS, and profilometry, as well as measurement of the electric contact resistance of the rubbed steel surfaces. The results revealed that the MIL exhibits better friction-reducing and antiwear performances than the as-received MF under varying test temperatures and loads. This is because the MIL participates in tribochemical reactions during the sliding process, and forms a boundary lubrication film composed of Dy2O3, FeS, FeSO4, nitrogen-containing organics, and thioether on the rubbed disk surface, thereby reducing the friction and wear of the frictional pair. However, the MF is unable to form a lubricating film on the surface of the rubbed steel at 25 °C, though it can form a boundary film consisting of Fe3O4 and a small amount of organics under high temperature. Furthermore, the excessive Fe3O4 particulates that accumulate in the sliding zone may lead to enhanced abrasive wear of the sliding pair.

Abstract Efficient and sustainable use of water-based lubricants is essential for energy efficiency. Therefore, the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from the viewpoint of resource conservation. In this study, water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature (around 25 °C) via in-situ surface modification. The tribological behavior of the as-synthesized Cu nanoparticles as an additive in distilled water was evaluated using a universal micro-tribotester. The results show that the as-synthesized Cu nanoparticles, as a water-based lubricant additive, can significantly improve the tribological properties of distilled water. In particular, the lowest friction coefficient of 0.06 was obtained via lubrication with a concentration of 0.6 wt% of Cu nanoparticles in distilled water, which is a reduction of 80.6% compared with that obtained via lubrication with distilled water alone. It is considered that some Cu nanoparticles entered the contact area of the friction pairs to form a complex lubricating film and prevent direct contact of the friction pairs. Furthermore, some Cu nanoparticles in the solution accelerate the heat transfer process, which also results in good tribological properties.

Facilitating ageing in place enables older people to remain in familiar places, namely their homes and neighbourhoods, as long as possible. However, urban redevelopment that includes the forced relocation of residents often makes ageing in place impossible. The present research examined how impending neighbourhood demolition affects the ageing in place of older people in Shenyang, China. Starting with the presscompetence model and related academic work concerning the influences of person– environment interaction on the wellbeing of older people, this paper discusses the impact of forced relocation and demolition on the meaning of home, the living arrangement and the role of family, and strategies to maintain the independence of older people. Transcript analysis of 54 semi-structured interviews with older residents revealed their ambivalent feelings towards the impending demolition. Long-term residence in declining neighbourhoods makes them feel rooted and enables them to develop their living strategies and plan for ageing in place. However, neighbourhood decline challenges their daily activities and they increasingly struggle to maintain their independence, which leads them to consider impending neighbourhood redevelopment as an opportunity to improve their living conditions. The impending forced relocation interrupts their place-based identity and living strategies and causes significant stress due to their lack of autonomy in the decision making on the relocation process, the move itself and their uncertainty regarding their post-relocation life. Implications for further research and policy are provided.

Hepatocellular carcinoma (HCC) is globally the second most common cause of cancer mortality. The majority of HCC patients are diagnosed at advanced stage disease for which no curative treatments exist. TGF-β has been identified as a potential therapeutic target. However, the molecular mechanisms mediating its functional switch from a tumor suppressor to tumor promoter in HCC and its interactions with other signaling pathways are poorly understood. Here, we demonstrate an aberrant molecular network between the TGF-β and c-KIT pathway that mediates the functional switch of TGF-β to a driver of tumor progression in HCC. TGF-β/SMAD2 signaling transcriptionally regulates expression of the c-KIT receptor ligand (stem cell factor [SCF]) with subsequent auto- and paracrine activation of c-KIT/JAK1/STAT3 signaling. SCF induces TGF-β1 ligand expression via STAT3, thereby forming a positive feedback loop between TGF-β/SMAD and SCF/c-KIT signaling. This network neutralizes TGF-β–mediated cell cycle inhibition and induces tumor cell proliferation, epithelial-to-mesenchymal-transition, migration, and invasion. Disruption of this feedback loop inhibits TGF-β tumor-promoting effects and restores its antiproliferative functions. Consistent with our in vitro data, we demonstrate SCF overexpression and its correlation to SMAD2 and STAT3 activation in human HCC tumors, advanced tumor-node-metastasis stages, and shorter survival. CONCLUSIONS: Canonical TGF-β and c-KIT signaling forms a positive, tumor-promoting feedback loop. Disruption of this loop restores TGF-β tumor suppressor function and provides the rationale for targeting the TGF-β/SCF axis as a novel therapeutic strategy for HCC.

The Chinese government has pursued rural land consolidation under the Building New Rural Communities (BNRC) initiative. The consolidation projects aim to address the hollowing village problem, improve the living standards of rural dwellers, and promote urban-rural integration. Rural villages with small populations and poor infrastructure are merged into a centralized rural community, and their inhabitants are resettled. The newly vacated buildings are then converted to agriculture land, which allows cities to expand under the “no net loss” land-use policy. Despite the significance of the initiative, both in terms of the scale of operation and the impacts on the affected households, there are few empirical studies that scrutinize this form of rural restructuring. Drawing on data collected via surveys and interviews, this paper examines the processes of land consolidation and its impacts on villagers. From a development-as-modernization perspective, we outline three main processes of land consolidation: village mergers and resettlement, land circulation to rural cooperatives, and rural industrial development. Overall, the effects of land consolidation on the livelihood of resettled villagers are positive. This system generally improves housing and living conditions through increased levels of off-farm employment and income, but there are a number of barriers that may hinder a villager’s ability to find different employment. Housing and neighborhood characteristics have significant effects on the life satisfaction of villagers.

A non-parametric Data Envelopment Analysis (DEA) technique was applied to investigate the degree of efficiency and efficiency change of prefecture-level cities in the North-East China from 2000 to 2012. Mean pure technical efficiency in a DEA model with the number of agriculture was 0.79, indicating that there is a big potential for a more efficient input utilization in agricultural productivity. Decomposition results of the Malmquist index indicated that the average productivity (MALM) growth at 8.0 percent annually over the entire period in the North-East China and the major source of growth was the technical change. In order to stimulate the productivity growth, more attention should be paid to improving the production efficiency. Polices should be enacted to increase the technical investment in agriculture, to enhance the rural education and research in agriculture which may help farmers to improve the agricultural efficiency and productivity. Given the limitations of the Statistical Yearbook data, some field investigation may carry out in future studies.

With rising income and the emergence of modern shopping centers in urban China, shopping trips by private car becomes more and more common, leading to higher carbon emissions in the transport sector. Encouraging car owners to shift transport mode from private car to public transport could achieve significant emissions reductions. This study estimate carbon emissions savings by shifting from private cars to public transport for shopping trips in urban China, using Shenyang, one of the largest cities in China, as a case study. Our results show that the average carbon emissions per shopper is 426.9 g, and the carbon emissions on weekends is 13% higher than weekdays. Moreover, shoppers travelling by private car emitted five times more carbon emission than those by public transport. We also found that car ownership gradually increased as accessibility to public transport decreased, and that more car owners chose to travel by private cars than public transport in areas with limited access. This study, thus, highlights the potential for high-quality public transport to reduce the transport sector’s carbon emissions in urban China.

Under the threat of food insecurity, the Chinese government has created plans and policies to stimulate soybean production. Despite government efforts to stimulate production, based on predictions, planned targets for soybean production are unlikely. Consequently, the predictions raise questions about farmers’ intentions to increase soybean cultivating area. In other words, farmers may not be willing to increase soybean. However, few researchers have studied soybean farmers’ intention and behavior. With these concerns in mind, this study analyzed the intention and factors that influence farmers’ choice of increasing soybean production as well as evaluating the differences in the decision making between commercial and subsistence farmers. This study collected data from 155 randomly selected families in 23 villages in the major soybean area in Heilongjiang Province. Results showed that 42.6% of the farmers expressed that they would expand soybean planting area, while the rest would insist on previous planting habits. The capacity to increase soybean production confronted many constraints. Farmers’ age, farm income, land topography, and ease of selling all positively influence farmers’ behavior. A significant difference in decision making between subsistence and commercial farmers was found. Subsistence farmers were more affected by land topography, agricultural insurance status, and satisfaction of soybean subsidies, whereas commercial farmers were more affected by farming experience and farm income. As a result, soybean policies should focus on increasing farmers’ income, promoting large-scale planting, training young farmers, innovation of agricultural insurance, and strengthening construction of agricultural infrastructure.

BackgroundLysine acetylation is a crucial type of protein post-translational modification, which is involved in many important cellular processes and serious diseases. However, identification of protein acetylated sites through traditional experiment methods is time-consuming and laborious. Those methods are not suitable to identify a large number of acetylated sites quickly. Therefore, computational methods are still very valuable to accelerate lysine acetylated site finding.ResultIn this study, many biological characteristics of acetylated sites have been investigated, such as the amino acid sequence around the acetylated sites, the physicochemical property of the amino acids and the transition probability of adjacent amino acids. A logistic regression method was then utilized to integrate these information for generating a novel lysine acetylation prediction system named LAceP. When compared with existing methods, LAceP overwhelms most of state-of-the-art methods. Especially, LAceP has a more balanced prediction capability for positive and negative datasets.ConclusionLAceP can integrate different biological features to predict lysine acetylation with high accuracy. An online web server is freely available at http://www.scbit.org/iPTM/.

Current literature highlights the role of commercial centers in cities in generating shopping trips and transport carbon emissions. However, the influence of the characteristics of commercial centers on consumer travel behavior and transport carbon emissions is not well understood. This study addresses this knowledge gap by examining shopping trips to eight commercial centers in Shenyang, China, and the CO2 emissions of these trips. We found that the locations and types of commercial centers strongly influence CO2 emissions. CO2 emissions per trip to commercial centers in the suburbs of Shenyang were on average 6.94% and 26.92% higher than those to commercial centers in the urban core and the inner city, respectively. CO2 emissions induced by wholesale centers were nearly three times higher than the lowest CO2 emissions of commercial centers in the inner city. These empirical results enhance our understanding of shopping-related transport carbon emissions and highlight the importance of optimizing urban space structure, in particular, the layout of commercial centers.

While previous studies have examined China’s changing industrial energy consumption at the national level, this study argues that it is more useful, from a policy standpoint, to conduct a regional-level analysis owing to the significant regional disparity in industrialisation in the country. This study focuses particularly on Northeast China, where the implementation of the Northeast Revitalisation Strategy in 2003 has contributed to rapid reindustrialisation, which has a serious implication for industrial energy consumption. We decompose the region’s energy consumption changes into activity, structure, and intensity effects. Our results show that the intensity effect is not the only negative factor impacting industrial energy consumption during 2003–2012. The structure effect also has a negative impact on industrial energy consumption between 2005 and 2012. However, the negative impact of the two factors is weakening and not strong enough to counter the positive impact of the activity effect. This result highlights the problem of uncoordinated policy-making in Northeast China. The development strategy, which still depends highly on traditional heavy industries, is in conflict with the national strategy of energy conservation. The two conflicting objectives of industrial revitalization and energy conservation must be reconciled for sustainability in the long term. The study concludes with policy recommendations on how to achieve such reconciliation.