Publications by authors named "Jian-Feng Peng"

Based on the method of tree-ring chronology, we established ring-width standard chrono-logies of and in Liangtaigou, Lixian County, western Sichuan Province, and their regional composite chronology (RC) to study the responses of radial growth of those two coniferous species to climate change, which provided a basis for the protection and mana-gement of forest ecosystems in this region under the background of global warming. The results showed that the RC contained the common climatic information of two individual chronologies, which had higher signal-to-noise ratio and expressed population signal. The correlation analysis showed that three chronologies had a good consistency in the response to climate factors.

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Taking plantations at different slopes in Songshan Mountains, Henan Province, China as subjects, we established different residual chronologies of in Paomaling (PML) and Junjifeng (JJF) and whole region (RC). The results showed that the chro-nological quality of PML was higher than that of JJF. Chronologies of PML and JJF had more climate information, which had significant positive relationship with mean temperature in current February, mean temperature and mean maximum temperature at the end of growing season (September-October), and significant negative relationship with mean maximum temperature in current May.

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Background: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a non-invasive technique which could monitor tumor morphology, blood vessel dynamics, and micro-environmental changes.

Purpose: To evaluate the value of DCE-MRI semi-quantitative parameters in monitoring the neoadjuvant chemotherapy (NAC) response of osteosarcoma.

Material And Methods: Twenty-five patients pathologically confirmed as osteosarcoma received four cycles of NAC followed by surgery.

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16S rRNA and functional genes were used as biomarker genes to investigate the temporal and spatial distribution of community diversity of () in the sediments of the Hunhe River by clone library technology. The dependence relationship between the physicochemical property of water and sediment samples and the diversity characteristics of the community were analyzed by multivariate direct gradient analysis. Among the examples collected in September 2014, the OTU number of the 16S rRNA gene of was 2-5, the Shannon-Wiener diversity index was 0.

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In order to quantitatively identify sources of nitrate pollution in Beijing urban area and provide effective guidance for relevant departments to control the pollution of Beijing rivers, δ¹⁵N-NO₃⁻ and δ¹⁸O-NO₃⁻ isotope tracing method was used to analyze the composition of nitrogen and oxygen stable isotopes from nitrate in Beijing urban river. Besides, stable isotope mixing model was adopted to track nitrogen sources of nitrate in Beijing urban rivers and the contribution rates of respective pollution sources were evaluated. The results showed that: (1) NO₃⁻-N pollution was the main inorganic nitrogen pollution in Beijing rivers and pollution of downstream was more serious than that of upstream.

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Excitation-emission matrix (EEM) fluorescence with self-organizing map was applied to characterize structural composition and spatial distribution of dissolved (DOM) and particulate (POM) organic matter from sediment pore water in a typical urban river. Ten sediment pore water samples were collected from the mainstream of Baitabuhe River in Shenyang City of northeast China, along a human impact gradient, i. e.

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By using the dendrochronology research methods, this paper developed the 1915-2011 tree ring-width standard chronology of the Huangshan pine (Pinus taiwanesis) at the north slope of western Dabie Mountains in the junction of Hubei, Henan and Anhui provinces. High mean sensitivity (MS) indicated that there was conspicuous high-frequency climate signals and high first-order autocorrelation (AC) showed there were significant lag-effects of tree previous growth. The higher signal-to-noise ratio (SNR) and expressed population signal (EPS) indicated that the trees had high levels of common climate signals.

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Nitrogen transformation and removal in a novel circular-flow corridor (CFC) wetland was simulated. A computer model covering 6 nitrogen forms, 3 media and 10 transferring pathways, was developed. The results show that the TN removal is attributed to zeolite adsorption (53.

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By use of the fluorescence in situ hybridization (FISH) and the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) methods, the diversity and similarity of microbial community during anaerobic sludge granulation were studied. The relative abundance and their succession of H2-producing acetogens (HPA), homoacetoges (HOMA) and methanogens were monitored. And the whole forming processes of micro-ecology were investigated correspondingly.

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Anaerobically digested swine wastewater contains high concentrations of phosphorus (P) and nitrogen (N). A pilot-scale experiment was carried out for nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization. In the pilot plant, a sequencing batch reactor (SBR) and a continuous-flow reactor with struvite accumulation devices were designed and employed.

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The changes of pH, COD, volatile fatty acids (VFA) and microbial morphology of the acidification process in an anaerobic baffled reactor (ABR) were investigated. And the population succession process of the anaerobic microorganisms was quantitatively analyzed by using the Fluorescent In situ hybridization technology (FISH). The results show that the ABR reactor is acidified gradually from the front to the back.

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Heavy metal contamination has become a worldwide problem through disturbing the normal functions of rivers and lakes. Sediment, as the largest storage and resources of heavy metal, plays a rather important role in metal transformations. This paper provides a review on the geochemical forms, affecting factors and remediation technologies of heavy metal in sediment.

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Based on the simulated results from N cycling and transformation model of duckweed pond, the influences of different major transfer pathways on various nitrogen removal performances are investigated. The effects of seasonal variations of water conditions on nitrogen transformations are determined. The simulated results show that nitrification and denitrification were the major removal pathways for nitrogen in duckweed pond, and the removal contributions of organic nitrogen sedimentation and ammonia volatilization for total nitrogen removal were less than 2.

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The performance of the Dongying multi-stage ponds-wetlands ecosystem was investigated in this work. Study of the removal of different pollutants (BOD(5), COD, SS, TP, TN, NH(3)-N, etc.) in different temperature seasons and different units in this system indicated that effluent BOD(5) and SS were constant to less than 11 mg/L and 14 mg/L throughout the experimental processes; but that the removal efficiencies of pollutants such as TP, TN, NH(3)-N, COD varied greatly with season.

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Interaction between an enhanced action of kinins and cytokines is accepted as important to the cardioprotective effect of angiotensin-converting-enzyme inhibitors. Kinins mediate their effects through B1 and B2 subtype receptors that may be modulated by cytokines including interleukin (IL)-1beta. We examined expression of kinin receptors and the effects of bradykinin (B2 agonist) and des-Arg10-kallidin (B1 agonist) on extracellular matrix components of adult rat cardiac fibroblasts with or without prior exposure to IL-1beta.

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Extracellular matrix (ECM) remodeling after myocardial infarction (MI) is an important determinant of cardiac function. Tumor necrosis factor-alpha (TNF-alpha) and angiotensin (Ang) II levels increase after MI and both factors affect fibroblast functions. The type 1 (AT1) receptor that mediates most Ang II effects is upregulated after MI in cardiac fibroblasts, and there is evidence that this is caused by TNF-alpha.

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Rats exposed chronically to a cold environment (5 degrees C/4 degrees F) develop hypertension. This cold-induced hypertension (CIH) is a non-genetic, non-pharmacological, non-surgical model of environmentally induced hypertension in rats. The renin-angiotensin system (RAS) appears to play a role in both initiating and/or maintaining the high blood pressure in CIH.

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Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta up-regulate type 1 angiotensin II receptor (AT(1)) mRNA and protein in cultured neonatal rat cardiac fibroblasts. The use of pharmacologic inhibitors and a degradation-resistant mutant I kappa B-alpha demonstrated that the transcription factor nuclear factor-kappa B (NF-kappa B) is necessary for cytokine-induced AT(1) up-regulation. The increase in AT(1) mRNA with TNF-alpha treatment is slow, reaching significance by 6-12 h and peaking by 24-48 h.

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