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This paper explores the interaction mechanism between urbanization and the ecological environment based on the unique correlation between urbanization and the ecological environment. BISE and Savizky-Golay algorithms are combined to establish the time series data, and for the characteristic curves of the EVI time response of the land cover, the spectral angle mapping method is combined with the minimum distance method to form the spectral angle-minimum distance classification method. The application of time series data involves calculating the time and spatial change of urban land cover and analyzing the evolution of urban ecological environment elements. Based on the temporal and spatial consistency test and land cover analysis of urban ecological environment construction, as well as the development of urbanization construction, relevant development paths are proposed. The comprehensive score of new urbanization in the four districts and one city of Hengyang City is concentrated towards 1.6, indicating that the level of economic development and the construction of new urbanization have reached coupling at different levels, respectively.

Abstract Insight into the mechanism of docetaxel resistance in breast cancer may help to improve prognosis. We aimed to investigate the role of N6-methyladenosine (m6A) and the METTL3/LINC00662/miR-186-5p pathway in regulating docetaxel resistance in triple negative breast cancer (TNBC). We have recruited 193 pathologically diagnosed TNBC patients from 2016 to 2017 in our hospital. Quantitative real-time PCR was used to evaluate the expression of LINC00662 and miR-186-5p both in vivo and in vitro. CCK8 tests were used to assess cell viability. ELISA was used for protein expression evaluation. Dual luciferase reporter gene assay and RNA pull-down were used to evaluate the interaction between LINC00662 and miR-186-5p. m6A levels were enhanced in breast cancer tissues and cells. LINC00662, miR-186-5p and METTL3 were differentially expressed in vivo, and METTL3 expression was associated with LINC00662 and miR-186-5p expression. LINC00662 and miR-186-5p were differentially expressed in vitro; LINC00662 promoted cell viability and decreased the apoptosis rate, whereas miR-186-5p inhibited cell viability and increased the apoptosis rate. Furthermore, we found that METTL3 regulated m6A levels in docetaxel-resistant breast cancer cells by regulating the expression of LINC00662. Moreover, LINC00662 and miR-186-5p regulated the cell viability rate of docetaxel-resistant breast cancer cells. Further experiments showed that LINC00662 directly interacted with miR-186-5p to exert biological functions; besides miR-186-5p could regulate the expression of METTL3. METTL3 promotes m6A levels and docetaxel resistance in breast cancer by regulating the expression of LINC00662 and miR-186-5p; more experiments are needed to clarify the role of m6A regulation in drug resistance.

Objective: To improve the accuracy of the results of cadmium （Cd） content in kelp （Laminaria japonica） by graphite furnace atomic absorption spectrometry （GF-AAS）. Methods: The concentration of Cd element in kelp sample was measured by using GF-AAS after microwave digestion according to the standard of GB 5009.15—2014. Combining with the experimental process and mathematical model, the possible sources of measurement uncertainty were firstly identified, then the components of each standard uncertainties were calculated, and finally each parameter of uncertainties was synthesized, and the whole uncertainty was evaluated. Results: when the value of Cd concentration in kelp was 0.202 mg/kg, the expanded uncertainty was 0.008 mg/kg （k=2）. Conclusion: The uncertainty of the method is mainly derived from the determination of Cd concentration in the sample solution, which is basically introduced by standard working solution preparation. Moreover, the uncertainty caused by the sample recovery rate is also large. So the quality control of the parameter of uncertainties should be strengthened in the future.

Objective To investigate the effect of necrotizing enterocolitis (NEC) at different severities on brain injury in neonatal mice. Methods Sixty 5-day old C57BL/6 mice were randomly divided into control group (CON group, n=20) and NEC group (n=40). The CON group was breeding with female mice and breast-fed. The NEC group was fed in an incubator, and induced by formula gavage feeding+hypoxia+oral lipopolysaccharide (LPS) to establish the model of NEC. In 4 d after NEC modeling, all pups were sacrificed by cervical decapitation. Their body weight was measured and general conditions were observed. HE staining was used to observe the pathological changes of intestinal tissue. NEC group was divided into mild NEC subgroup and severe NEC subgroup according to the intestinal injury score of ileocecus. Nissl staining was employed to further observe the pathological changes of the corresponding brain tissue. The correlation between the severity of intestinal injury and the number of nerve cells was analyzed with Pearson analysis. The mRNA levels of the inflammatory factors interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) in brain tissues were measured with quantitative real-time PCR (RT-qPCR). Enzyme-linked immunosorbent assay (ELISA) was adopted to detect the protein contents of IL-1β, IL-6 and TNF-α in brain tissues. Immunofluorescence assay was conducted to detect the number of activated microglia and astrocytes in the hippocampus. Results Compared with CON group, the NEC group had decreased activities and lower body weight (3.84±1.25 vs 1.76±0.26 g, P < 0.05), and serious intestinal damage. The number of nerve cells in the hippocampus were significantly reduced in the NEC group than the CON group (P < 0.05), so was in the severe NEC subgroup than that the mild NEC subgroup (P < 0.05). Correlation analysis showed that the pathological changes of brain were negatively correlated with the severity of intestinal injury (r=- 0.943, P < 0.001). When compared with the CON group, the mRNA and protein levels of IL-1β, IL-6 and TNF-α in brain tissues were significantly elevated (P < 0.05), and the numbers of activated microglia and astrocytes were also significantly increased in the NEC group (P < 0.05), especially in the severe NEC subgroup (P < 0.05). Conclusion NEC can lead to acute brain injury in neonatal mice, and the severity of damage is related to the severity of intestinal injury, which may be related to the increase of neuroinflammation.

Objective To investigate the effect of direct current (DC) electric field on the proliferation of human adipose-derived stem cells (hASCs) in vitro. Methods The fat tissue obtained in operation was digested with zymogen to prepare hASCs. After the cell culture was passaged to the third generation, the hASCs were inoculated in a 6-well plate. After 24 h, the cells were cultured under a stimulation of 0, 50, 100, 150 and 200 mV/mm DC electric field, at a frequency of 1 h/d for 3 continuous days. Cell morphology and growth were observed under an inverted microscope. Cell counting and CCK8 assay were carried out to measure cell proliferation. Flow cytometry was performed to detect the expression of stem cell phenotype markers, CD105, CD73, CD90, CD14, CD34, CD31 and CD45. The effect of DC electric field stimulation was observed after differentiation induction. Western blotting was used to detect the expression of proteins related to cell proliferation in stimulated and unstimulated cells. Results The proliferation rate and absorbance value were significantly higher in the cells after 50, 100 and 150 mV/mm stimulation than those without (all P < 0.01). When the stimulation intensity of the DC electric field was increased to 200 mV/mm, the proliferation rate was significantly lower (P < 0.001), but the absorbance value was statistically higher than those of the 0 mV/mm stimulation (P < 0.05). The stimulation also resulted in remarkably higher expression of CD105, CD73 and CD90, and lower expression of CD14, CD31, CD34 and CD45. Moreover, the hASCs could differentiate into bone cells and adipocytes with and without DC electric field stimulation, but the stimulated cells had faster differentiation than those without. Compared with the unstimulated cells, the expression of cell proliferation related protein p-ERK1/2 was significantly increased in the stimulated cells (P < 0.01). Conclusion The DC electric field promotes the proliferation of hASCs probably by regulating the phosphorylation of ERK, but has no effect on the biological characteristics of the stem cells.

Objective To investigate the clinical effectiveness of stromal vascular fraction gel (SVF-gel) containing human adipose derived stem cells (ADSCs) in the treatment of adherent scar. Methods A retrospective analysis was carried out on the patients with adherent scars meeting our inclusion criteria and undergoing the treatment of gel injection during June 2018 and June 2020. The SVF-gel was prepared from the lipoaspirates sucked from the abdomen or the thigh followed by filtration, centrifugation and emulsion, and then injected into the adherent scars (at an interval of 2 mm for every needle puncture, SVF-gel 0.02 mL for every dose). Small amount of granular adipose tissues and SVF-gel were digested, cultured and identified. The scar hardness and thickness were measured for every patient preoperatively and 6 months postoperatively. Patient and observer scar assessment scale (POSAS) was used to evaluate scar condition, and patient satisfaction was investigated. Results There were 8 patients enrolled in this study, with a total of 10 adherent scars and the area of depression of 5.56±4.50 cm2. The injection volume of SVF-gel under the adherent scar was 3.90±3.00 mL. The results of morphological observation showed that short spindle cells grew in both SVF-gel and granular fat after digestion, and the over 95% obtained cells expressed the specific markers of mesenchymal stem cells, CD73, CD90 and CD105. At the same time, the number of primary cells cultured in same volume of SVF-gel was larger than the number from the granular fat tissue. Differentiation study found the growth of adipose-like cells in vitro, which were positive to oil red O staining. The scar hardness was decreased from 48.13±20.59 shore units preoperatively to 30.96±15.66 shore units in 6 months postoperatively(P < 0.05), and the scar skin thickness was increased from 2.00±0.60 mm to 2.72±0.63 mm (P < 0.05). In 6 months after operation, the appearance and activity of scar skin were significantly improved, and no complications were observed. The scores of patient scar assessment scale (PSAS) and observer scar assessment scale (OSAS) were 12.0±2.8 and 13.7±3.9 respectively, and the patient satisfaction score was 4 to 5, with an average of 4.6. Conclusion Our prepared SVF-gel contains more active ADSCs. Its injection can improve the local depression and scar texture in the adherent scar and achieve good satisfaction in the patients.

Objective To investigate the causes of keloid invasive growth by comparing the expressional differences of E-cadherin, vimentin, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1 (HIF-1α), and the epidermal histological differences among keloid marginal region, central region and normal skin. Methods This study enrolled 16 patients undergoing keloid resection in our department from October 2019 to August 2020, with a total of 16 keloid tissues, and 9 patients who required partial normal skin resection during the operation, with a total of 9 normal skin tissues. Hematoxylin and eosin (H&E) staining was used to observe the tissue morphology, and immunohistochemical staining and Western blot assay were used to detect the expression of E-cadherin, vimentin, VEGF and HIF-1α in above tissues. Results There was obvious abnormality and heterogeneity in the epidermal layer of keloids. The marginal epidermal subdivided into fine-branch-like and then clearly penetrated into the dermis, forming a houndstooth-like appearance, while the central epidermal became thick and flat; Immunohistochemical staining and Western blot assay showed that the expression level of E-cadherin was significantly weaker in the marginal and central epidermal of keloid tissue than in the normal skin (P < 0.05), with that in the margin weaker than the center (P < 0.05); The levels of vimentin, HIF-1α and VEGF were significantly higher in the keloid tissue than normal skin (P < 0.05), and those in the margin took the highest (P < 0.05). Conclusion Marginal epidermis of keloid clearly extends to the dermis in branched appearance, with active epithelium-to-mesenchymal transition (EMT), highly expressed HIF-1α, VEGF and abundant microvessels. The underlying mechanism may be related to the aggressive growth of the keloid edge, and HIF-1α might be the key factor.

Based on the generalized finite element method and the substructure method,a dynamics model of the double gearbox transmission system coupled by the diaphragm coupling is established. The dynamic meshing forces and the dynamic bearing forces are calculated through the Fourier method,which are then compared with the results without considering the coupled effects. The result shows that the coupled effects on meshing pairs are small,while effects on bearings are more significant especially on those close to the coupling,and when considering the coupled effects,the dynamic meshing force and dynamic bearing forces emerge other frequencies,but the amplitudes of them are small.

Taking the single-stage gear rotor system as the research object,a generalized finite element model with total freedom is established. The calculation speed and the accuracy of Newmark method and Fourier series method are compared in solving dynamics equation of gear system. An improved Fourier series method is proposed,which has less calculation time and higher calculation accuracy.

With the maturity of information technologies such as big data, blockchain, industrial Internet, and artificial intelligence, the Sino-US trade war continues to escalate.It can be predicted that after the Sino-US trade war in goods, a “digital trade war” may have begun quietly.On the one hand, the key to Internet issues is data governance rules, which are related to digital trade and digital economy, and are the key to future national competitiveness;on the other hand, the impact of the trade war on China’s trade in goods is also an issue that needs to be discussed.The article found through research that the negative impact of the Sino-US trade war on China is gradually showing. The scale of China’s trade import and export has shrunk, and a lot of trade opportunities have been lost.The prediction of “internet fragmentation” is becoming a reality.I analyzed the countermeasures to deal with the trade war from the aspects of conducting trade negotiations, expanding internal demand, and handling data governance issues.

BackgroundThe Atribacterota are widely distributed in the subsurface biosphere. Recently, the first Atribacterota isolate was described and the number of Atribacterota genome sequences retrieved from environmental samples has increased significantly; however, their diversity, physiology, ecology, and evolution remain poorly understood.ResultsWe report the isolation of the second member of Atribacterota, Thermatribacter velox gen. nov., sp. nov., within a new family Thermatribacteraceae fam. nov., and the short-term laboratory cultivation of a member of the JS1 lineage, Phoenicimicrobium oleiphilum HX-OS.bin.34TS, both from a terrestrial oil reservoir. Physiological and metatranscriptomics analyses showed that Thermatribacter velox B11T and Phoenicimicrobium oleiphilum HX-OS.bin.34TS ferment sugars and n-alkanes, respectively, producing H2, CO2, and acetate as common products. Comparative genomics showed that all members of the Atribacterota lack a complete Wood-Ljungdahl Pathway (WLP), but that the Reductive Glycine Pathway (RGP) is widespread, indicating that the RGP, rather than WLP, is a central hub in Atribacterota metabolism. Ancestral character state reconstructions and phylogenetic analyses showed that key genes encoding the RGP (fdhA, fhs, folD, glyA, gcvT, gcvPAB, pdhD) and other central functions were gained independently in the two classes, Atribacteria (OP9) and Phoenicimicrobiia (JS1), after which they were inherited vertically; these genes included fumarate-adding enzymes (faeA; Phoenicimicrobiia only), the CODH/ACS complex (acsABCDE), and diverse hydrogenases (NiFe group 3b, 4b and FeFe group A3, C). Finally, we present genome-resolved community metabolic models showing the central roles of Atribacteria (OP9) and Phoenicimicrobiia (JS1) in acetate- and hydrocarbon-rich environments.ConclusionOur findings expand the knowledge of the diversity, physiology, ecology, and evolution of the phylum Atribacterota. This study is a starting point for promoting more incisive studies of their syntrophic biology and may guide the rational design of strategies to cultivate them in the laboratory. Video Abstract.

Limiting climate change to 1.5°C and achieving net-zero emissions would entail substantial carbon dioxide removal (CDR) from the atmosphere by the mid-century, but how much CDR is needed at country level over time is unclear. The purpose of this paper is to provide a detailed description of when and how much CDR is required at country level in order to achieve 1.5°C and how much CDR countries can carry out domestically. We allocate global CDR pathways among 170 countries according to 6 equity principles and assess these allocations with respect to countries biophysical and geophysical capacity to deploy CDR. Allocating global CDR to countries based on these principles suggests that CDR will, on average, represent ∼4% of nations total emissions in 2030, rising to ∼17% in 2040. Moreover, equitable allocations of CDR, in many cases, exceed implied land and carbon storage capacities. We estimate ∼15% of countries (25) would have insufficient land to contribute an equitable share of global CDR, and ∼40% of countries (71) would have insufficient geological storage capacity. Unless more diverse CDR technologies are developed, the mismatch between CDR liabilities and land-based CDR capacities will lead to global demand for six GtCO2 carbon credits from 2020 to 2050. This demonstrates an imperative demand for international carbon trading of CDR.

The multi-information fusion method of health monitoring based on evidence theory is used to study the problem of equipment fault diagnosis. The multi-information of fault monitoring is fused by the evidence theory and the reliability of the relevant evidence can be judged according to the ambiguity and uncertainty of the fault monitoring signal. Also it can determine the importance and reliability of the evidence from different sources. The data from multi-information fusion has higher reliability and accuracy which provides more reliable data for fault diagnosis.

The methane (CH4) emissions from municipal solid waste (MSW) landfills in China in 2007 were estimated based on database of the three-dimensional emission factors matrix and point sources, by an IPCC recommended FOD (firstorder decay) model. The location, capacity and age of landfills constitute the three dimensions of the emission factors matrix, which were obtained by laboratory analysis and in situ investigation. Key parameters such as waste composition, degradable organic carbon ratio, CH4 correction factor, oxidation factor and recovery rate, were carefully analyzed in terms of these three dimensions. The point sources database consists of 2,107 MSW landfills in cities and towns of China in 2007. The results show that the CH4 emissions from MSW landfills were 1.186 Mt in 2007. Compared with the CH4 emissions of 2.20 Mt in 2005, the significant discrepancy mainly comes from statistical data of landfills, e.g., number of landfills and amount of waste disposed in landfills. CH4 emissions were lower than 700 t for most of the landfills, whereas there were 279 landfills with emissions larger than 1,000 t, and only 10 landfills with emissions larger than 10,000 t. Jiangsu province ranks the largest emitter with 98,700 t while Tibet is the smallest emitter with 2,100 t. In general, the emissions from eastern provinces, such as Jiangsu, Guangdong and Zhejiang, were larger than those from western provinces, such as Ningxia, Tibet and Qinghai. Citation: Cai, B.-F., Liu, J.-G., Gao, Q.-X., et al., 2014. Estimation of methane emissions from municipal solid waste landfills in China based on point emission sources. Adv. Clim. Change Res. 5(2), doi: 10.3724/SP.J.1248.2014.081.

Urban agglomeration is not only an important carrier of China's new urbanization strategy, but also a new regional unit for the country to participate in global competition and international division of labor. At present, China's regional spatial governance model is undergoing a major change, from the original administrative division management to the type of regional spatial governance. Based on the important extension characteristics of urban agglomerations, this paper classifies 23 urban agglomerations in China with the idea of comprehensive classification, and obtains the index system and clustering results of type classification, which provides scientific basis for the planning guidance of spatial pattern optimization and classification management of urban agglomerations in China. Referring to the scale and degree of agglomeration of mature urban agglomerations in the world, based on the four characteristics of urban agglomerations, the index system is constructed. Fuzzy C-means clustering (FCM) method is used to quantitatively classify Chinese urban agglomerations into five types.