Evolution of the Pearl River and its Implication for East Asian Continental Landscape Reversion

As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are of great significance in revealing the East Asian continental landscape reorganization during the Late Cenozoic.Based on published data,’source-to-sink’provenance analyses allow systematic deliberation on the birth and evolutionary history of the Pearl River.Close to the Oligocene/Miocene boundary,an abrupt shift in the sedimentary composition indicates significant westward and northward expansion of the river’s watershed area,followed by the establishment of a near-modern fluvial network.This sedimentary change generally concurred with a series of regional geological events,including the onset of the Yangtze throughflow,large-scale development of the loess plateau,and formation of the northwestern arid zone and Asian Monsoon system.These major changes in the geology-climate-ecoenvironment system are in close response to the process of the Cenozoic Xizang(Tibetan)Plateau uplift.Consequently,the East Asian continental landscape and most of midCenozoic drainage systems underwent critical reversion into east-tilting,or east-flowing networks.

Storage Stability in Reversion Mutation of a Rice Line Devoid of LOX-1, 2 Acquired by Ion Beam Irradiation

The effect of absence of lipoxygenase isoenzyme （LOX） on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 （LOX-1） or lipoxygenase isoenzyme-2 （LOX-2） generated by ion beam irradiation from Wanjian2090 and reversion mutant RM1297 with LOX-1 and LOX-2 were subjected to an accelerated-aging experiment. Shanyou63 （with LOX-1 and LOX-2 ） served as control. Results showed that the germination and dehydrogenase activity decreased while the electrical conductivity and free fatty acid content increased in all varieties with accelerated aging. In 1297 that lacked LOX-1 and 2, there were slight changes in germination, dehydrogenase activity, membrane permeability and free fatty acid content during the thirty-day accelerated-aging experiment. But in varieties with LOX-1 and LOX-2, significant changes were observed, suggesting that LOX-1, 2 might be a definite factor which influenced seed lifespan. This study also indicates that ion beam irradiation may be used as mutagen to generate mutant and reversion mutants for biological study and could become a new direction in ion beam application.

The satellite reversion of dissolved organic carbon (DOC) based on the analysis of the mixing behavior of DOC and colored dissolved organic matter: the East China Sea as an example

The retrieval of dissolved organic carbon （DOC） distribution by remote sensing is mainly based on the em- pirical relationship of DOC concentration and colored dissolved organic matter （CDOM） concentration in many literatures. To investigate the nature of this relationship, the distributions and mixing behaviors of DOC and CDOM are reviewed in the world＇s major estuaries and bays. It is found that, generally, the C- DOM concentration is well correlated with the salinity in most estuaries, while DOC usually shows a non- conservative behavior which leads to a weak correlation between the DOC concentration and the CDOM concentration. To establish a good satellite reversion of the DOC concentration, the East China Sea（ECS） was taken as an example, and the mixing behavior of DOC and CDOM as well as the influence of biogeo- chemical processes were analyzed except for the physical mixing process with the data from late autumn （November, 2010） and winter （December, 2009） cruises. In the two ECS cruises, the CDOM concentration was found to be tightly correlated with the salinity, influenced little by the photochemical or biological pro- cesses. The data from the winter cruise show that DOC followed a conservative mixing along the salinity gradient, while in the late autumn cruise it was significantly affected by the biological activities, resulting in a poor correlation between the DOC and the CDOM. Accordingly, an improved DOC algorithm （CSDM） was proposed： when the biological influence was significant （Chl a greater than 0.8 μg/dm3）, DOC was retrieved by the conservative and biological model, and if the conservative mixing was dominant （Chl a less than 0.8 μg/dm3）, the direct DOC concentration and CDOM concentration relationship was used. Based on the pro- posed algorithm, a reasonable DOC distribution for the ECS from satellite was obtained in this study, and the proposed method can be applied to the other large river-dominant marginal sea.

Toward sustainable desertification reversion:A case study in Horqin Sandy Land of northern China

Desertification reversion is an interactive process involving climate, land use change, and water processes. In order to reveal the relationship between desertification reversion and these factors, we analyzed historical data on precipitation, air temperature, desertified land changes, underground water tables, and water body changes in Naiman County in the central part of Horqin Sandy Land. Our analysis showed that during 1961-2010 the annual precipitation fluctuated dramatically and has decreased fairly consistently in recent years. The air temperature increased by 0.50-1.25℃, and the minimum temperature increased more obviously. The desertified land area increased from 42,300 km^2 in 1959 to 62,000 km^2 in 1985, and then declined to about 50,000 km^2 in 2010. The underground water tables have been lowered by about 10 m in the past 30 years, and declined more rapidly in recent years. Desertified land is significantly related to the amount of total cropland, and underground water tables are signifcantly correlated with annual precipitation and the amount of irrigated cropland. Therefore, it is necessary to pursue sustainable desertification reversion without compromising the capacity for local development and restoration of degraded land, through application of appropriate management measures for improving water availability in this region.

Spatial heterogeneity of soil water content in the reversion process of desertification in arid areas

Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological systems in arid areas.The spatial heterogeneity of soil water content is a major soil property,and a focus of soil science and hydrology.On the southern edge of the Tengger Desert,sample plots were selected from mobile sand dunes in desertified lands that had been enclosed for 5,15 and 25 years,respectively.This study explored the dynamic and spatial heterogeneity of soil water content in these different layers of soil that were also in the reversion process of desertification.The results showed that the soil water content of the mobile sand dunes was highest when in the initial stages of the reversion process of desertification,while the soil water content in the 0-20 cm,20-40 cm and 40-60 cm layers of soil was 1.769%,3.011%,and 2.967% respectively,presenting a restoring tendency after 25 years of enclosure.There were significant differences,as a whole,in the soil water content among different restoration stages and different soil layers,respectively.Changes in soil water content,in different soil layers,at different restoration stages,exhibited exponential or spherical patterns.The spatial distribution of soil water content exhibited a mosaic patch pattern with obvious spatial heterogeneity.The ratio of the heterogeneity of spatial autocorrelation to gross spatial heterogeneity was greater than 50%.The gross spatial heterogeneity of the 0-20 cm layer of soil improved gradually,while those of the 20-40 cm and 40-60 cm layers improved initially,then weakened in the reversion process of desertification.This study revealed that restoration with sand-binding vegetation reduced soil water content,and increased its spatial heterogeneity in arid areas.However,after 25 years of vegetation-soil system restoration,the soil water content started to increase and its spatial heterogeneity started to weaken.These results will further benefit the understanding of the ecological mechanism between soil water and sand-binding vegetation.

Multiphase-field simulation of austenite reversion in medium-Mn steels

Medium-Mn steels have attracted immense attention for automotive applications owing to their outstanding combination of high strength and superior ductility.This steel class is generally characterized by an ultrafine-grained duplex microstructure consisting of ferrite and a large amount of austenite.Such a unique microstructure is processed by intercritical annealing,where austenite reversion occurs in a fine martensitic matrix.In the present study,austenite reversion in a medium-Mn alloy was simulated by the multiphase-field approach using the commercial software MICRESS®coupled with the thermodynamic database TCFE8 and the kinetic database MOBFE2.In particular,a faceted anisotropy model was incorporated to replicate the lamellar morphology of reversed austenite.The simulated microstructural morphology and phase transformation kinetics(indicated by the amount of phase)concurred well with experimental observations by scanning electron microscopy and in situ synchrotron high-energy X-ray diffraction,respectively.

Reversion of weak-measured quantum entanglement state

We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels.The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path.It can reverse the perturbed entanglement intensity evolution to its original state.Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly.In the process we can get the classical information described by information gain from the quantum system through weak measurement operation.On the other hand,in order to realize complete reversibility,the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process.

Reversion Mutation in Dark Variants of Luminous Bacteria and Its Application in Gene Toxicant Monitoring

The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.

Molecular mechanism of carvedilol in attenuating the reversion to fetal energy metabolism during cardiac hypertrophy development

Objective: To explore the molecular regulation mechanism of carvedilol in attenuating the reversion back towards fetal energy metabolism during the development of cardiac hypertrophy induced by coarctation of abdominal aorta (CAA) in male Wistar rats. Methods: Hemodynamic and ventricular remodeling parameters, free fatty acid content in the serum were measured in the experimental animals at 16 weeks after the surgical CAA, the rats receiving carvedilol intervention (CAR) after CAA, and those with sham operation (SH). The expressions of muscle carnitine palmitoyltransferaseⅠ (M-CPTⅠ) and medium chain acyl-CoA dehydrogenase (MCAD) mRNA in the cardiac myocytes from every group were studied with RT-PCR. Results: Significant left ventricular hypertrophy were observed in the rats 16 weeks after coarctation operation (P<0.05), together with significant free fatty acids accumulation and downregulation of M-CPTⅠ and MCAD mRNA (P<0.05) in CAA group. Carvedilol at a dose of 30 mg/kg/d for 12 weeks inhibited the left ventricular hypertrophy induced by pressure overload and enhanced the gene expressions of rate-limiting enzyme (M-CPTⅠ) and key enzyme of fatty acid (MCAD) in the CAR group compared with CAA group (P<0.05). Conclusion: Pressure overload-induced hypertrophy in CAA rats causes the reversion back towards fetal enery metabolism, that is, downregulates the expressions of rate-limiting enzyme and key enzyme of fatty acid oxidation. The intervention therapy with carvedilol, a vasodilating alpha- and beta-adrenoreceptor antagonist, attenuates the reversion of the metabolic gene expression to fetal type through upregulating M-CPTⅠ and MCAD mRNA expressions. Thus, carvedilol may exert cardioprotective effects on heart failure by the mechanism of preserving the adult metabolic gene regulation.

Reversion of Bioluminescent Bacteria (Mutatox^(TM)) toTheir Luminescent State upon Exposure to OrganicCompounds, Munitions, and Metal Salts

Mutatox is a new genotoxicity bioassay which uses as the endpoint the bioluminescence produced on reversion of a dark strain of the marine bacterium Vibrio fischeri ±S9.Reversion can occur by several mechanisms, including base substitution, frame-shift, SOS induction, and DNA intercalation. For screening, Mutatox provides many advantages over the Salmonella trphimurium (Ames) assay: it requires minimal sterility, employs a shorter incubation period, and does not require culture maintenance. Eighteen organic chemicals (phenol, polynuclear aromatic hydrocarbons, nitrotoluenes, others), Na3PO4, and 4 genotoxic metals (Cu2+, Ni2+, As3+, Cd2+) were tested. Most of the organic compounds positive in S. typhimurium assays were positive in Mutatox. None of the metals was genotoxic in V. fischeri, possibly due to poor uptake from the saline medium

A New Mean Reversion Model of Close-End Fund

On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end fund mean reversion model. Meanwhile, this paper validates the mean reversion time sequence for consecutive 54 week data of fund market. The result indicates that this model can effectively prove that Chinese close-end fund market follows the biased random walk. The research also proves that the fund discount does have mean reversion tendency and averagely the fund with high discount has a higher excess yield than that of the fund with low discount. The mean excess yield and the ratio between discount rate deviation and standard deviation demonstrate a descending relationship. The optimum investment period based on ＂mean reversion＂ is one month. Consequently this model provides a new arbitrage method through the discount of close-end fund.

Efficient Strip-Mode SAR Raw-Data Simulator of Extended Scenes Included Moving Targets Based on Reversion of Series

The Synthetic Aperture Radar(SAR)raw data generator is required to the evaluation of focusing algorithms,moving target analysis,and hardware design.The time-domain SAR simulator can generate the accurate raw data but it needs much time.The frequency-domain simulator not only increases the efficiency but also considers the trajectory deviations of the radar.In addition,the raw signal of the extended scene included static and moving targets can be generated by some frequency-domain simulators.However,the existing simulators concentrate on the raw signal simulation of the static extended scene and moving targets at uniform speed mostly.As for the issue,the two-dimensional signal spectrum of moving targets with constant acceleration can be derived accurately based on the geometric model of a side-looking SAR and reversion of series.And a frequency-domain algorithm for SAR echo signal simulation is presented based on the two-dimensional signal spectrum.The raw data generated with proposed method is verified by several simulation experiments.In addition to reveal the efficiency of the presented frequency-domain SAR scene simulator,the computational complexity of the proposed method is compared with the time-domain approach using the complex multiplication.Numerical results demonstrate that the present method can reduce the computational time significantly without accuracy loss while simulating SAR raw data.

REVERSION OF MULTIDRUG RESISTANCE IN THE P-GLYCOPROTEIN POSITIVE BREAST CANCER CELL LINE(MCF-7/ADR) BY INTRODUCTION OF HAMMERHEAD RIBOZYME

A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.

Inhibition of mammalian target of rapamycin induces phenotypic reversion in three-dimensional cultures of malignant breast epithelial cells

Inhibition of mammalian target of rapamycin (m- TOR) is a potential method for cancer treatment. Effects of rapamycin (RAP) on the reversion of malignant breast epithelial cells were investigated on three-dimensional (3D) basement membrane extract (BME) cultures. Through continuous exposure to 20 nM of RAP, cell colony size was significantly reduced in 3D BME cultures of malignant breast epithelial cells, while normal cell colony size appeared unaffected. In unfixed 3D BME cultures of normal and RAP-treated malignant breast epithelial cells, the presence of luminal cell death was confirmed by ethidium bromide and propidium iodide labeling. Increased structural organization was observed by im- munofluorescence staining of F-actin and β-catenin in RAP-treated malignant breast epithelial cells. In monolayer cultures of normal and malignant breast epithelial cells, continuous exposure to 20 nM of RAP increased caspase 3/7 activity and decreased proliferation. Reverse transcriptase polymerase ch- ain reaction (RT-PCR) array analysis indicated a fold increase in the expression of a number of proteins related to polarity, cell-cell adhesion, and cell-matrix adhesion in the presence of RAP. Our data showed that phenotypic reversion of malignancy can be ach- ieved through RAP exposure on 3D BME cultures. This 3D BME culture system will provide correct microenvironments for observing the effects of other mTOR inhibitors on phenotypic reversion of malignant breast epithelial cells.

Study to Solve the Problem of Color Reversion in Refined Soybean Oil

This study carried out on the soybean oil samples taken from the processing lines during refining process (degumming, neutralization, bleaching and deodorization process) for crude soybean oil as well as on color reversed oil after deodorization step during storage for several hours to study the physical and chemical properties (color, refractive index (RI), free fatty acid (FFA), peroxide value (PV), p-Anisidine value (p-AV), total oxidative (TOTOX) value, oxidative stability (OS), saponification value (SV), iodine value (IV), unsaponifiable matter (unsap. %), soap content, minerals, waxes, total phenols content, K232 and k270 nm), the fatty acids composition, sterol compound, total tocopherols and their components (α, β, γ and δ tocopherol) and tocored compound for these oils and to find out the reason for the color reversion after a short period from storage for the deodorized soybean oil. Citric acid has been added (0.2%) to each color reversed and neutralized soybean oils, then procedure of bleaching and deodorization process on them, and studied its effect on the physical and chemical properties for them specially the color units (red and yellow), tocopherols contents and tocored compound. The results showed that refining process for soybean oil caused to a gradual decrease in values of AV, oxidative stability, IV, wax, % Unsapo., K232 and K270 nm, total polyphenols, minerals (P, Ca and Mg), total tocopherols and their compounds (α, β, γ and δ tocopherol) and also caused decrease in all sterol components, but they showed a few differences in percentages of fatty acids as result refining process. Color values (red and yellow unites) recorded gradually decreased during refining process, but these values were increased in deodorized soybean oil after storage (color reversed soybean oil). Reduction of α, β, γ and δ tocopherol contents was found to be linearly with the increase of red and yellow color units (color darking). The tocored is responsible for the color reversion phenomenon, where as maximum amount of tocored was in crude soybean oil 169.2 ppm, which gradually decreased during refining process 120.35, 99.82, 20.25, and 8.46 ppm, respectively, but it was found to be 46.5 ppm in color reversed soybean oil. Addition of citric acid (0.2%) related to the removal of tocored from soybean oil during the bleaching and deodorization process of soybean oil before and after color reversion in parallel with the significant decrease in the color values.

Reversion of Incommensurate Modulation in Cubic Lazurite: Example of Reversible Forced Equilibrium?

The sample of cubic lazurite, collected in the Baikal region, with incommensurately 3D modulated (ITM) structure has been studied by the method of high-temperature X-ray powder diffraction. At short time of annealing in high-temperature diffraction experiment the modulation recovery proceeds during cooling down the sample to room temperature. The identity of the period of both initial and recovered modulation demonstrates that the system has a structural memory. The acquired results are interpreted through comparison of thermal behavior of lazurite, sodalite and quartz structures. It is supposed that two kinetically different and thermally activated processes proceed under heating: 1) reversible framework expansion due to Si-O-Al angle increase, and 2) equalizing of periodic local distortions via the diffusion-controlled transfer of cage ions between adjacent subcells. The second process seems to be much slower than the first one, especially at lower temperatures. With increasing temperature, both processes are activated. However, the framework expands more rapidly than the cage clusters migrate, and the periodic distortions of the framework are aligned. Under lower temperatures, the framework shrinks and again accommodates to the configuration of cage cations (clusters), which may be changed at high temperature and sufficient time or may not at lower temperature, short time, unfavorable SO2 fugacity values. In the first case the modulation disappears entirely, while in the second case it arises again. The probable reason for ITM formation is the balance of counteracting energetic terms: the elastic strain energy of structure deformation and the energy of cluster ordering providing the state of forced equilibrium. The excess free energy due to structure distortion is compensated by the increment associated with the cluster ordering process. However, no significant variations in sulphur anion speciation for different degrees of modulation retention were observed by XPS S 2p. This may be due to the ordering of Na- and Ca-containing clusters rather than the clusters with different sulphur species. ITM reversion is considered as an example of reversible forced equilibrium with completely reproducible forcing factor.

Thermal Reversion of Plant Phytochromes

Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development.Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion,also termed dark reversion.Although the term“dark reversion”is justified by historical reasons and frequently used in the literature,“thermal reversion”more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the review.Thermal reversion is a critical parameter for the light sensitivity of phytochrome-mediated responses and has been studied for decades,often resulting in contradictory findings.Thermal reversion is an intrinsic property of the phytochrome molecules but can be modulated by intra-and intermolecular interactions,as well as biochemical modifications,such as phosphorylation.In this review,we outline the research history of phytochrome thermal reversion,highlighting important predictions that have been made before knowing the molecular basis.We further summarize and discuss recent findings about the molecular mechanisms regulating phytochrome thermal reversion and its functional roles in light and temperature sensing in plants.

Enhanced tensile properties of a reversion annealed 6.5Mn-TRIP alloy via tailoring initial microstructure and cold rolling reduction

The feasibility of improving the overall performance of medium Mn steels was demonstrated via tailoring the initial microstructure and cold rolling reduction. The combined effects of cooling patterns after hot rolling （HR） and cold rolling （CR） reductions show： （1） as the cooling pattern varied from furnace cooling （FC） to oil quenching （OQ）, the intercritically annealed microstructure was dramatically refined and the fraction of recrystallized ferrite dropped, regardless of CR reductions. This resulted in both high yield/ultimate tensile strengths （YS/UTS） but low total elongation to fracture （El）; （2） as the CR reduction increased from 50% to 75%, the OQ-samples after annealing exhibited a more refined microstructure with relatively higher fractions of retained austenite and sub-structure, leading to higher YS and UTS but lower El; whereas the FC samples appeared to exhibit little difference in overall tensile properties in both cases. The differences in microstructural evolution with cooling patterns and CR reductions were explained by the calculated accumulated effective strain （eAES）, which was considered to be related to degrees of recovery and recrystallization of the deformed martensite （α＇）. The optimal tensile properties of -1 GPa YS and -40 GPa.% UTSxEI were achieved in the OQ-50%CR annealed samples at 650 ℃ for 1 h. This was quite beneficial to large-scale production of ultra-high strength steels, owing to its serious springback during heaw cold working.

Cu-assisted austenite reversion and enhanced TRIP effect in maraging stainless steels

Control of the formation and stability of reverted austenite is critical in achieving a favorable combination of strength,ductility,and toughness in high-strength steels.In this work,the effects of Cu precipitation on the austenite reversion and mechanical properties of maraging stainless steels were investigated by atom probe tomography,transmission electron microscopy,and mechanical tests.Our results indicate that Cu accelerates the austenite reversion kinetics in two manners:first,Cu,as an austenite stabilizer,increases the equilibrium austenite fraction and hence enhances the chemical driving force for the austenite formation,and second,Cu-rich nanoprecipitates promote the austenite reversion by serving as heterogeneous nucleation sites and providing Ni-enriched chemical conditions through interfacial segregation.In addition,the Cu precipitation hardening compensates the strength drop induced by the formation of soft reverted austenite.During tensile deformation,the metastable reverted austenite transforms to martensite,which substantially improves the ductility and toughness through a transformation-induced plasticity(TRIP)effect.The Cu-added maraging stainless steel exhibits a superior combination of a yield strength of~1.3 GPa,an elongation of~15%,and an impact toughness of~58 J.

Overexpression of a reversion-related protein in the revertant RR cells

The cDNA insert of the plasmid p14-6[1] is found to be the 3’-untranslatcd region (3’-UTR) of the transcription factor for human interleukin-6, NF-IL6. This 3’ -DTK is actively transcribed in the revertant cell line RR, which contains the p14-6 plasmid integrated into its genomic DNA. Simultaneously a protein specifically bound to this 3’-UTR is expressed in significantly larger amounts. Its overexpression is apparently related to the reversion of the malignant cellular phenotype. The properties of this protein, named BNF, and possible reasons for its overexpression are discussed, and hypothesis on the mechanism of reversion of the RR cells is proposed.