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Alternate freezing and thawing enhanced the sediment and nutrient runoff loss in the restored soil of the alpine mining area

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Journal of Mountain Science 2022年第6期19卷 1823-1837页

作者： LI Fa-Yong LUO Ren-jie YOU Yong-jun HU Xue-fei QIAN Xiao-yan ZHANG Peng-yan WANG Shan LI Guo-yu KAMEL Mohamed Eltohamy College of Water Resources and Architectural Engineering Tarim UniversityAral City 843300China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Water Relations and field Irrigation Department Agricultural and Biological Research DivisionNational Research CentreCairo 12622Egypt

This study highlights the influence of freezing-thawing processes on soil erosion in an alpine mine restoration area. Accordingly, a series of simulation experiments were conducted to investigate runoff, sediment, and nutrient losses, and potential influencing factors under freeze-thaw(FT) conditions. Three FT treatments(i.e., 0, 3, and 5 FT cycles), and two soil moisture contents(SMCs;i.e., 10% and 20% SMC on a gravimetric basis) were assessed. The runoff, sediment yield, ammonia nitrogen(AN), nitrate nitrogen(NN), total phosphorus(TP), and dissolved phosphorus(DP) losses from runoff were characterized under different rainfall durations. The fitting results indicated that the runoff rate and sediment rate, AN, NN, TP, and DP concentrations in runoff could be described by exponential functions. FT action increased the total runoff volume and sediment yield by 14.6%–26.0% and 8.8%–35.2%, respectively. The runoff rate and sediment rate increased rapidly with the increment of FT cycles before stabilizing. At 20% SMC, the total runoff volume and sediment yield were significantly higher than those at 10% SMC. The loss curves of AN and NN concentrations varied due to differences in their chemical properties. FT action and high SMC promoted AN and NN losses, whereas the FT cycles had little effect. FT action increased TP and DP losses by 60.2%–220.1% and 48.4%–129.8%, respectively, compared to cases with no FT action;the highest TP and DP losses were recorded at 20% SMC. This study provides a deep understanding of freezing-thawing mechanisms in the soils of alpine mine restoration areas and the influencing factors of these mechanisms on soil erosion, thereby supporting the development of erosion prevention and control measures in alpine mine restoration areas.

关键词： Freezing and thawing Mine restoration area nitrogen loss Phosphorus loss Rainfall simulation Soil moisture content

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Effects of Different Types of Sludge on Soil Microbial Properties:A field Experiment on Degraded Mediterranean Soils

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Pedosphere 2010年第6期20卷 681-691页

作者： D.TARRASóN G.OJEDA O.ORTIZ J.M.ALCAIZ centre for Ecological Research and Forestry Applications Autonomous University of Barcelona IMAR-Coimbra Interdisciplinary centre Department of ZoologyUniversity of Coimbra

The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P < 0.01; loamy sand soil: P < 0.001) and carbon mineralization coefficient (loam soil: P < 0.01; loamy sand soil: P < 0.001). Furthermore, on loamy sand soil, the plots amended with TDS showed the highest microbial metabolic quotient (qCO 2 ) (P < 0.05). This study revealed that the addition of sludge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.

关键词： basal respiration composted sludge soil microbial biomass thermally dried sludge

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Multifaceted nature of membrane microdomains in colorectal cancer

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World Journal of Gastroenterology 2011年第6期17卷 681-690页

作者： Kristina A Jahn Filip Braet Australian centre for Microscopy and Microanalysis The University of Sydney

Membrane microdomains or lipid rafts are known to be highly dynamic and to act as selective signal transduction mediators that facilitate interactions between the cell's external and internal *** rafts play an important mediating role in the biology of cancer:they have been found in almost all existing experimental cancer models,including colorectal cancer (CRC),and play key regulatory roles in cell migration,metastasis,cell survival and tumor *** paper explores the current state of knowledge in this field by highlighting some of the pioneering and recent lipid raft studies performed on different CRC cell lines and human tissue *** this literature review,it becomes clear that membrane microdomains appear to be implicated in all key intracellular signaling pathways for lipid metabolism,drug resistance,cell adhesion,cell death,cell proliferation and many other processes in *** signal transduction pathways seem to originate directly from those peculiar lipid islands,thereby orchestrating the colon cancer cells' state and *** confirmed by recent animal and preclinical studies in different CRC models,continuing to unravel the structure and function of lipid rafts-including their associated complex signaling pathways-will likely bring us one step closer to better monitoring and treating of colon cancer patients.

关键词： Actin Caveolae Cytoskeleton Combined imaging Detergent-resistant membranes Drug targeting Electron microscopy Lipid domains Membrane rafts Prognosis Staging Tomography Lipid-mediated therapy

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Mechanism of metastasis by membrane type 1-matrix metalloproteinase in hepatocellular carcinoma

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World Journal of Gastroenterology 2005年第40期11卷 6269-6276页

作者： Ying-Chi Ip Siu-Tim Cheung Ka-Ling Leung Sheung-Tat Fan centre for the Study of Liver Disease and Department of Surgery

AIM To investigate the precise role of membrane type 1-matrix metalloproteinase （NTI-NNP） in hepatocellular carcinoma （HCC） metastasis. METHODS- Human HCC cells Hep3B with overexpression of MTT-MMP were established by stable transfection, and compared with control cells carrying the empty vector. Cells were examined in vivo for their differences in the metastatic ability of athymic nude mice, and analyzed in vito for their differences in invasion ability by invasion chamber coated with Matrigel, adhesion towards collagen I and migration through culture chamber. Cell proliferation and apoptosis in adherent and suspension status were evaluated by MTr and flow cytometry analysis. RESULTS We found that overexpression of MT1-MMP could increase intrahepatic metastasis in nude mice with orthotopic implantation of HCC cells （incidence of 100% [MT1-MMP transfectants] vs 40% [vector control transfectants], P〈0.05）. NT1-MMP could also enhance cell invasion through Natrigel （107.7 vs 39.3 cells/field, P〈0.001）, adhesion towards matrix （0.30 vs 0.12 absorbance unit at 540 nm, P〈0.001）, cell migration （89.3 vs 39.0 cells/field, P〈0.001）, and cell proliferation （24.3 vs 40.5 h/doubling, P〈0.001）. We also observed that NTI-NNP supported cell survival （71.4% vs 23.9%, P〈0.001） with reduced apoptosis （43.7% vs51.0%, P〈0.05） in an attachment-free environment. CONCLUSION： MT1-MMP overexpression could enhance metastasis. In addition to its active role in matrix degradation during tumor invasion, MT1-MMP enhances tumor cell survival upon challenge of detachment, which is important during metastasis when cells enter the circulation.

关键词： MT1-MMPIMMP14 Liver cancer Invasion Metastasis

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Analysis of process variations impact on the single-event transient quenching in 65 nm CMOS combinational circuits

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Science China(Technological Sciences) 2014年第2期57卷 322-331页

作者： WANG TianQi XIAO LiYi ZHOU Bin QI ChunHua Micro-electric centre Harbin Institute of Technology

Single-event transient pulse quenching （Quenching effect） is employed to effectively mitigate WSET （SET pulse width）. It en- hanced along with the increased charge sharing which is norm for future advanced technologies. As technology scales, param- eter variation is another serious issue that significantly affects circuit＇s performance and single-event response. Monte Carlo simulations combined with TCAD （Technology Computer-Aided Design） simulations are conducted on a six-stage inverter chain to identify and quantify the impact of charge sharing and parameter variation on pulse quenching. Studies show that charge sharing induce a wider WSET spread range. The difference of WSET range between no quenching and quenching is smaller in NMOS （N-Channel Metal-Oxide-Semiconductor field-Effect Transistor） simulation than that in PMOS＇（P-Channel Met- N-Oxide-Semiconductor field-Effect Transistor）, so that from parameter variation view, quenching is beneficial in PMOS SET mitigation. The individual parameter analysis indicates that gate oxide thickness （TOXE） and channel length variation （XL） mostly affect SET response of combinational circuits. They bring 14.58% and 19.73% average WSET difference probabilities for no-quenching cases, and 105.56% and 123.32% for quenching cases.

关键词： single-event transient (SET) parameter variation Monte Carlo simulation quenching effect charge share

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Influence of Sputtering Pressure on the Structure and Mechanical Properties of Nanocomposite Ti-Si-N Thin Films

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Journal of Materials Science & Technology 2010年第8期26卷 673-678页

作者： Vipin Chawla R.Jayaganthan Ramesh Chandra Department of Metallurgical and Materials Engineering & centre of Nanotechnology Indian Institute of Technology Roorkee Nano Science Laboratory Institute Instrumentation CentreIndian Institute of Technology Roorkee

Nanocomposite Ti-Si-N thin films have been deposited on Si （100） substrate by direct current/radio frequency （DC/RF） magnetron sputtering. The effect of varying deposition parameters on the structure and mechanical properties of Ti-Si-N films has been investigated by characterization techniques such as X-ray dif- fraction （XRD）, field emission scanning electron microscopy （FE-SEM）, atomic force microscopy （AFM） and nanoindentation, respectively. XRD analysis of the thin films exhibit all （111）, （200） and （220） peaks initially with varying sputtering pressure, but （111） peak dominates at higher sputtering pressure. The crystallite size calculated from XRD peaks shows that it increases with increasing sputtering pressure. Microstructural analy- sis reveals that the dense blurred grains transform into uniform grains in the films and shows porosity with increasing sputtering pressure. The surface roughness of the Ti-Si-N films increases with varying sputtering pressure. The hardness and Youngrs modulus values of Ti-Si-N films are 33.7 and 278.6 GPa, respectively, with 0.7 Pa sputtering pressure but it decreases with further increase in sputtering pressure due to an increase in porosity of the films.

关键词： Ti-Si-N films Nanoindentation Microstructural characterization

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PREDICTION OF LOADING DISTRIBUTION AND HYDRODYNAMIC MEASUREMENTS FOR PROPELLER BLADES IN A RIM DRIVEN THRU-STER

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Journal of Hydrodynamics 2012年第1期24卷 50-57页

作者： CAO Qing-ming HONG Fang-wen TANG Deng-hai HU Fang-lin LU Lin-zhang China Ship Scientific Research centre Wuxi 214082China

This article presents an approach which employs a commercial Reynolds-Averaged Navier-Stokes（RANS）solver to predict the steady wake field and loading distributions for a rim driven *** different cases of propeller blades are chosen to be calculated with the presented *** propeller blade radial circulation and chordwise circulation density distributions are *** maximum radial circulation is found at the blade tip,which is different from conventional shaft driven *** numerical results indicate that there is no tip leakage vortex in rim driven *** there exist the tip joint vortex and the root region *** characteristics are calculated by taking rim surface effect into *** the predicted results the second case in this paper is selected as the final one to perform hydrodynamic *** calculation results with empirical rim surface corrections are compared with the *** shows that the developed numerical method can well predict hydrodynamic performances of the rim driven thruster.

关键词： rim driven thruster Reynolds-Averaged Navier-Stokes(RANS)solver wake field radial circulation chordwise circulation density hydrodynamic experiment

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Simulation Analysis and Experimental Study of Defect Detection Underwater by ACFM Probe

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China Ocean Engineering 2013年第2期27卷 277-282页

作者：李伟陈国明张传荣刘涛 centre for Offshore Engineering and Safety Technology China University of Petroleum

This article studies the application of the alternating current field measurement （ACFM） method in defect detection for underwater structures. Numerical model of the ACFM system is built for structure surface defect detection in seawater environment. Finite element simulation is performed to investigate rules and characteristics of the electromagnetic signal distribution in the defected area. In respect of the simulation results, underwater artificial crack detection experiments are designed and conducted for the ACFM system. The experiment results show that the ACFM system can detect cracks in underwater structures and the detection accuracy is higher than 85%. This can meet the engineering requirement of underwater structure defect detection. The results in this article can be applied to establish technical foundation for the optimization and development of ACFM based underwater structure defects detection system.

关键词： ACFM underwater structure defect detection simulation analysis experimental study

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Precise Seismic Substructural Model of the Eocene Chorgali Limestone in the Turkwal Oil field, Central Potwar, Pakistan

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1711-1720页

作者： Khawar Ashfaq AHMED Sarfraz KHAN Mahmood SULTAN UMAIR Bin Nisar Kalim ULLAH Al-Hseinat MU’AYYAD Comsats University Islamabad(CUI)Pakistan National centre of Excellence in Geology University of PeshawarPeshawar25130KPPakistan centre for Earthquake Studies National Centre for Physics(NCP)IslamabadPakistan centre for Climate Research and Development(CCRD) CUIIslamabadPakistan Department of Geology University of JordonAmmanJordan

The precise seismic substructural interpretation of the Turkwal oil field in the Central Potwar region of district Chakwal of Pakistan has been carried out. The research work was confined to the large fore-thrust that serves as an anticlinal structural trap through ten 2 D seismic lines. A precise seismic substructural model of the Eocene Chorgali Limestone with precise orientation of thrust and oblique slip faults shows the presence of a huge fracture, which made this deposit a good reservoir. The abrupt surface changes in dip azimuth for the Eocene Chorgali Limestone verifies the structural trends and also the presence of structural traps in the Turkwal field. The logs of three wells(Turkwal deep X-2, Turkwal-01 and Fimkassar-01) were analyzed for petrophysical studies, well synthetic results and generation of an Amplitude Versus Offset(AVO) model for the area. The AVO model of Turkwal deep X-2 shows abrupt changes in amplitude, which depicts the presence of hydrocarbon content. Well correlation technique was used to define the overall stratigraphic setting and the thickness of the reservoir formation in two wells, Turkwal-01 and Turkwal deep X-2. The Eocene Chorgali Limestone in Turkwal-01 is an upward thrusted anticlinal structure and because of the close position of both wells to the faulted anticlinal structure, its lesser thickness differs compared to Turkwal deep X-2. The overall results confirm that the Turkwal field is comparable to several similar thrust-bound oil-bearing structures in the Potwar basin.

关键词： 2D seismic well correlation fore-thrust structural traps AVO model Eocene Chorgali Limestone and Basement Potwar

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Stem cells for spinal cord injuries bearing translational potential

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Neural Regeneration Research 2018年第1期13卷 35-42页

作者： Kyriakos Dalamagkas Magdalini Tsintou Alexander M.Seifalian Department of Tissue Engineering Harvard Medical School Nanotechnology & Regenerative Medicine centre Division of Surgery and Interventional Science University College London Nanotechnology & Regenerative Medicine Commercialisation centre (Ltd). The London Bio Science Innovation Centre

Spinal cord injury （SCI） is a highly debilitating neurological disease, which still lacks effective treatment strategies, causing significant financial burden and distress to the affected families. Nevertheless, nanotechnology and regenerative medicine strategies holding promise for the development of novel therapies that would reach from bench to bedside to serve the SCI patients. There has already been significant progress in the field of cell-based therapies, with the clinical application for SCI, currently in phase II of the clinical trial. Stem cells （e.g., induced pluripotent stem cells, fetal stem cells, human embryonic stem cells, and olfactory ensheathing cells） are certainly not to be considered the panacea for neural repair but, especially when combined with rehabilitation or other combinatorial approaches using the help of nanotechnology, they seem to be the source of some of the most promising and clinical translatable cell-based therapies that could help solving impactful problems on neural repair.

关键词： spinal cord injury stem cells neuroregeneration plasticity repair

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