In this paper, we introduce two subgradient extragradient-type algorithms for solving variational inequality problems in the real Hilbert space. The first one can be applied when the mapping
f
is ...strongly pseudomonotone (not monotone) and Lipschitz continuous. The first algorithm only needs two projections, where the first projection onto closed convex set
C
and the second projection onto a half-space
C
k
. The strong convergence theorem is also established. The second algorithm is relaxed and self-adaptive; that is, at each iteration, calculating two projections onto some half-spaces and the step size can be selected in some adaptive ways. Under the assumption that
f
is monotone and Lipschitz continuous, a weak convergence theorem is provided. Finally, we provide numerical experiments to show the efficiency and advantage of the proposed algorithms.
The quantitative identification of rural land functions serves as a basis for rural land planning, coordinated spatial development, and control capacity improvement and is significant for rural ...transformation and sustainable development. This paper constructs an analysis framework to identify and evaluate “production-living-ecological” space (PLES) in rural areas of central and western China. On the Loess Plateau, which was taken as the study area, a combination of qualitative and quantitative analysis was completed to determine framework indicators and their thresholds. Resource and environmental carrying capacity and land suitability were measured through GIS spatial analysis under different land functional orientations. This sought to recognize production space (PS), living space (LS), and ecological space (ES) in rural areas, reveal their distribution patterns on the Loess Plateau, and determine alternative areas for future land use. The results indicate that the PS and LS of the Loess Plateau rural land show a relatively low resource and environmental carrying capacity but vary significantly in different functional regions. The space distribution of PS and LS with higher carrying capacity shows obvious consistency. Although the Loess Plateau has vast sustainable land for development, the intensity of development should be carefully controlled. Additionally, significant regional differences remain in rural PLES, so reasonable future rural land planning should be formulated according to the PLES pattern. This study provides a scientific basis for promoting coordinated development of Loess Plateau rural areas and implementing a rural revitalization strategy. It is also a reference for identifying PLES and its coordinated spatial development in rural central and western China.
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•A carbothermal preparation method of porous carbon-encapsulated iron (Fe@PC) was established.•Fe@PC with strong magnetism and good regeneration ability showed high Cr(VI) removal ...efficiency.•Effect of pore structure and surface chemistry of Fe@PC on its Cr(VI) removal ability was studied.
Porous carbon-encapsulated iron (Fe@PC) composite was prepared through carbothermal reduction of Fe(NO3)3 and starch. The porous carbon could envelop iron and protect it from being oxidized, while iron endow the composite with ferromagnetism, so that Fe@PC can be easily recovered by an external magnetic field. The prepared material was used to remove trace Cr(VI) in polluted water. The Cr(VI) removal process of Fe@PC, which highly depended on both microporous structure and reducing groups, was significantly affected by the preparation conditions and solution pH. At 25°C, Fe@PC-750 could remove 99.5% Cr(VI) from simulated wastewater containing 5.00mgL−1 Cr(VI) with an initial pH of 7, and the residual concentration of Cr(VI) was as low as 0.02mgL−1. The XPS analysis results confirmed that Cr(VI) could be reduced to Cr(III) after being adsorbed, and the elevation of pH would enhance the reduction ability of Fe@PC. The Fe@PC composite with high Cr(VI) removal efficiency, strong magnetic property and desirable regeneration ability can be practically applied in the removal of trace heavy metal pollutants from wastewater.
A fibrous adsorbent with amino-terminated hyperbranch structure (PP-AM-HBP-NH
) was prepared by grafting hyperbranched polyamine (HBP-NH
) onto the acrylamide-modified polypropylene (PP) fibers. The ...grafting of AM on PP fibers provided the active sites for introducing HBP-NH
onto the PP fibers. This kind of "grafting to" procedure to synthesize hyperbranch-structured fiber could overcome the disadvantages of stepwise growth procedure, avoiding the complicated synthesis process and the requirement of strict experimental conditions. The grafted HBP-NH
was three-dimensional dentritic architecture and had a large number of pores existing within the grafted polymers, which is favorable for CO
molecules to diffuse into the HBP-NH
. Therefore, the as-prepared PP-AM-HBP-NH
fibers showed a high adsorption capacity (5.64 mmol/g) for CO
in the presence of water at 25 °C, and the utilization efficiency of alkyl amino groups could reach 88.2%, demonstrating that the hyperbranched structure of adsorbents can greatly promote adsorption capacity and efficiency. This could be attributed to better swelling properties and lower mass transfer resistance to CO
of the hyperbranched adsorbent. PP-AM-HBP-NH
also showed excellent regeneration performance, and it could maintain the same adsorption capacity for CO
after 15 recycle numbers as the fresh adsorbent.
Controllable conversion of biomass to value-added carbon materials is attractive towards a wide variety of potential applications. Herein, hydrothermal treatment and KOH activation are successively ...employed to treat the cheap and abundant camellia oleifera shell as a new carbon raw material. It is shown that this stepwise activation process allows the production of porous nitrogen-doped carbon with optimized surface chemistry and porous structure compared to the counterparts prepared by a single activation procedure. Benefiting from the modulated porous structure, the as-produced porous nitrogen-doped carbon electrode delivered a high reversible capacity of 1080 mAh g
at a current density of 100 mA g
, which is 3.3 and 5.8 times as high as that of the carbon materials prepared by bare hydrothermal treatment or KOH activation, respectively. Moreover, the optimized surface composition of the porous nitrogen-doped carbon endows it with a highest initial Coulombic efficiency among the three samples, showing great potentials for practical applications. This work is expected to pave a new avenue to upgrade biomass to carbon materials with tunable surface properties and microstructures for target applications.
Promoting white adipose tissue (WAT) “browning” and brown adipose tissue (BAT) activation could contribute to increasing energy expenditure. We explored the mechanisms by which the natural compound ...rutin induced adipose tissue differentiation and ameliorated obesity in vivo and in vitro. 3T3-L1 preadipocytes were cultured in adipogenic differentiation media with/out rutin. Male C57BL/6 mice (n = 6) were fed a high-fat diet (HFD) for 12 weeks with/out rutin. In HFD-fed mice, rutin treatment significantly inhibited weight gain, improved the metabolic profile of plasma samples, decreased the weights of epididymal WAT (eWAT), inguina WAT (iWAT), and liver, and adipocyte size. Furthermore, rutin also increased the expression of uncoupling protein 1 (Ucp-1) and other thermogenic markers in the WAT and BAT. In 3T3-L1 cells, rutin effectively reduced the formation of lipid droplets, stimulated the expression of thermogenic markers, and reduced the expression of adipogenic genes. Additionally, rutin markedly upregulated the AMP-activated protein kinase (AMPK) pathway, and these effects were diminished by treatment with the AMPK inhibitor compound C (CC). Pretreatment with the calmodulin-dependent protein kinase kinase β (CaMKKβ) inhibitor STO-609 blocked the induction of thermogenic markers in 3T3-L1 cells by rutin. Our results indicated that rutin increased energy consumption, induced WAT “browning” and BAT activation, and thus was a promising target for the development of new therapeutic approaches to improve adipose tissue energy metabolism.
Aims
This study aimed to evaluate the role of seed bank during ecosystem transitions from arid grassland to shrubland.
Methods
We explored the aboveground vegetation, seed bank and soil environmental ...factors at 29 sites along a moisture gradient that served as a space-for-time substitution in the Qaidam Basin on the Tibetan Plateau to test whether changes seed bank composition or changes in the ability of the seed bank to restore aboveground vegetation could lead to ecosystem transition.
Results
We found that the composition of the aboveground vegetation presented nonlinear changes with decreased soil moisture and showed an inflection point in the threshold zone on the spatial scale of ecosystem transition from arid grassland to shrubland; however, an inflection point was not observed for the seed bank. Surprisingly, we also found the similarity between the aboveground vegetation and seed bank decreased obviously when soil moisture crosses the critical threshold.
Conclusions
Our results suggest that the transition from arid grassland to shrubland ecosystem is not caused by changes of the seed bank composition but by the inhibition of the seed bank's restorability to aboveground vegetation. Future work on changes in vegetation composition and species diversity with ecosystem transitions should consider the belowground seed bank.
Criminals targeting and exploiting older adults in online environments are of great concern. This study systematically retrieved and analyzed articles on the psychological characteristics of older ...adult victims of online fraud. First, we found that there was no evidence that older adults were more prevalent than other individuals of other ages among online fraud victims, and current researchers have focused more on why older adults are easy targets for fraud (susceptibility to being cheated). Second, research on psychological factors of older adults' susceptibility to online fraud has mainly focused on cognitive function, trust traits, and other personality traits, such as social loneliness, the Big Five personality traits, and self-control. Among them, most researchers claim that the cyber-cheating of older adults may be due to a decline in their cognitive function. However, there has not been a consensus on how cognitive function and physical and mental conditions affect older people who are cheated. Third, techniques (i.e., methods and techniques used by fraudsters) and experience (i.e., familiarity with internet technology or fraud) may be related to the susceptibility of older adults to fraud, and these studies have also not yet generated a consensus supported by reliable data. Based on the above research uncertainties, we propose that fraud prevention and control strategies for older adults should be applied with caution.
In this paper, we firstly constructed a theoretical framework based on major function-oriented zones (MFOZs). Then taking the Loess Plateau (LP) as the study area, we revealed the spatio-temporal ...differences and influencing factors of carbon emission equity by using the carbon equity model,
Theil
index, and Geo-detector. The results showed that: (1) From 2000 to 2017, the carbon equity of the Loess Plateau showed a downward trend, but the ecological carbon equity remained above 2.3, which was significantly higher than the economic carbon equity. (2) The ecological carbon equity in the Loess Plateau increased from the core of urban agglomeration to the periphery. The spatial pattern of economic carbon equity changed from low in the northeast and high in the southwest to low in the north and high in the south. The ecological support coefficient and economic contribution coefficient of provincial capital cities and their surrounding districts remained low since 2000. (3) The equity of carbon emissions in each function-oriented zone in the Loess Plateau was compatible with its orientation. The ecological carbon equity of the key ecological functional zones (KEFZs) was significantly higher than that of the key development zones (KDZs) and the major agricultural production zones (MAPZs), while the economic carbon equity of the KDZs was significantly higher than that of the MAPZs and the KEFZs. (4) The formation and evolution of the spatial differentiation pattern of carbon equity in the Loess Plateau was the result of the long-term interaction effects of geographic location, social economy, science and technology level, and policy system. Among them, eco-environmental protection policy, government financial support, and geographical location are the key driving factors for the spatial pattern of ecological carbon equity. Geographical location, social economic level, and science and technology level are the key factors driving the spatial pattern of economic carbon equity. According to this study, to achieving carbon equity on the Loess Plateau region, what the key approaches are to fully implement the planning of MFOZs, design differentiated regional carbon compensation mechanisms, improve energy efficiency and ecological environment capacity, and build a collaborative regional carbon emission governance system. This research can not only provide an effective framework for analysing the carbon equity, but also offer policy implication for promoting carbon emission reduction and achieving high-quality development goals in the ecologically fragile areas.
Although right‐sided colorectal cancer (CRC) shows a worse prognosis than left‐sided CRC, the underlying mechanism remains unclear. We established patient‐derived organoids (PDOs) from left‐ and ...right‐sided CRCs and directly compared cell proliferation and invasion capability between them. We then analyzed the expression of numerous genes in signal transduction pathways to clarify the mechanism of the differential prognosis. Cell proliferation activity and invasion capability in right‐sided cancer PDOs were significantly higher than in left‐sided cancer PDOs and normal PDOs, as revealed by Cell Titer Glo and transwell assays, respectively. We then used quantitative RT‐PCR to compare 184 genes in 30 pathways among right‐sided and left‐sided cancer and normal PDOs and found that the TIMP1 mRNA level was highest in right‐sided PDOs. TIMP1 protein levels were upregulated in right‐sided PDOs compared with normal PDOs but was downregulated in left‐sided PDOs. TIMP1 knockdown with shRNA significantly decreased cell proliferation activity and invasion capability in right‐sided PDOs but not in left‐sided PDOs. Moreover, TIMP1 knockdown significantly decreased pFAK and pAkt expression levels in right‐sided PDOs but not in left‐sided PDOs. A database analysis of The Cancer Genome Atlas revealed that TIMP1 expression in right‐sided CRCs was significantly higher than in left‐sided CRCs. Kaplan–Meier survival analysis showed significantly shorter overall survival in high‐TIMP1 patients versus low‐TIMP1 patients with right‐sided CRCs but not left‐sided CRCs. Our data suggest that TIMP1 is overexpressed in right‐sided CRCs and promotes cell proliferation and invasion capability through the TIMP1/FAK/Akt pathway, leading to a poor prognosis. The TIMP1/FAK/Akt pathway can be a target for therapeutic agents in right‐sided CRCs.
Our study suggests that TIMP1 is overexpressed in the right‐sided colorectal cancer, and promotes cell proliferation and invasion capability through TIMP1/FAK/Akt pathway, leading to poor prognosis.