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Residual oil zones (ROZs) have large potential for CO2 enhanced oil recovery (EOR) and geologic storage. During CO2 injection, the migration of CO2 in ROZs controls the performance of both EOR and storage. However, it has not been clearly visualized and understood that how geological heterogeneity factors control the transport of CO2 in ROZs. In this study, the oil recovery performance and geologic storage potential during continuous CO2 injection in a representative ROZ are studied based on geostatistical modelling and high-fidelity three-phase flow simulation. We examined the influence of autocorrelation length of permeability, global heterogeneity (Dykstra–Parsons coefficient), and permeability anisotropy on cumulative oil recovery and CO2 retention fraction. Simulation results indicate that, as the permeability autocorrelation length increases, the cumulative oil recovery and CO2 storage efficiency decrease. This results from the accelerated migration of CO2 along high permeability zones (i.e., gas channeling). The increase in global heterogeneity and permeability anisotropies can lead to low oil recovery and poor CO2 sequestration performance, depending on the degree of CO2 channeling. The net utilization ratio of CO2 (CO2 retained/oil produced) unfavorably increases with both autocorrelation length and Dykstra–Parsons coefficient, but decreases with the increase in kv/kh. Such a decrease is attributed to enlarged swept volume induced by gravity override. The study provides important implications for field-scale CO2 EOR and storage applications in ROZs. [ABSTRACT FROM AUTHOR]

The quality of senesced leaves is a strong driver for litter decomposition and nutrient cycling in terrestrial ecosystems. The effects of global change factors and ecosystem management strategies on nutrients and stoichiometry of mature leaves have been well established. In contrast, we still know little about their effects on the quality of senesced leaves, which would be different from that of mature leaves due to the occurrence of nutrient resorption during leaf senescence. We examined the effects of nitrogen (N) addition (5.25 g N m-2 yr-1), prescribed fire (with four frequencies, including no burning and burning every 1, 2, 4 years), and their interactions on N and phosphorus (P) concentrations and N:P ratios in senesced leaves of five dominant species in a temperate steppe of northern China. Nutrient concentrations and N:P ratios of senesced leaves varied substantially among the five species. Nitrogen addition increased N concentrations and N:P ratios but had no significant effect on P concentrations. Fire significantly increased N and P concentrations and N:P ratios in senesced leaves across all species. The effects of fire depended on its frequency. There was no interaction between N addition and fire in affecting nutrient concentrations and stoichiometry of senesced leaves. Our results suggested that N addition and fire can potentially alter litter quality by changing senesced leaves nutrient status and stoichiometric ratios, with an indirect effect on litter decomposition and ecosystem nutrient cycling in the grassland ecosystems. [ABSTRACT FROM AUTHOR]

Background Spray cut chrysanthemum is a vital flower with high ornamental value and popularity in the world. However, the excessive quantity of pollen dispersal of most spray cut chrysanthemum is an adverse factor during its flowering stage, and can significantly reduce its ornamental value and quickly shorten its vase life. More seriously, excessive pollen grains in the air are usually harmful to people, especially for those with pollen allergies. Therefore, in order to obtain some valuable information for developing spray cut chrysanthemum with lessdispersed or non-dispersed pollen in the future breeding programs, we here investigated the factors affecting quantity of pollen dispersal of spray cut chrysanthemum with four cultivars, i.e. 'Qx-097', 'Noa', 'Qx-115', and 'Kingfisher', that have different quantity of pollen dispersal. Results 'Qx-097' with high quantity of pollen dispersal has 819 pollen grains per anther, 196.4 disk florets per inflorescence and over 800,000 pollen grains per inflorescence. The corresponding data for 'Noa' with low quantity of pollen dispersal are 406, 175.4 and over 350,000, respectively; and 219, 144.2 and nearly 160,000 for 'Qx-115' without pollen dispersal, respectively. 'Kingfisher' without pollen dispersal has 202.8 disk florets per inflorescence, but its anther has no pollen grains. In addition, 'Qx-097' has a very high degree of anther cracking that nearly causes a complete dispersal of pollen grains from its anthers. 'Noa' has a moderate degree of anther cracking, and pollen grains in its anthers are not completely dispersed. However, the anthers of 'Qx-115' and 'Kingfisher' do not crack at all. Furthermore, microsporogenesis and pollen development are normal in 'Qx-097', whereas many microspores or pollen degenerate in 'Noa', most of them abort in 'Qx-115', and all of them degrade in 'Kingfisher'. Conclusions These results suggest that quantity of pollen dispersal in spray cut chrysanthemum are mainly determined by pollen quantity per anther, and capacity of pollen dispersal. Abnormality during microsporogenesis and pollen development significantly affects pollen quantity per anther. Capacity of pollen dispersal is closely related to the degree of anther dehiscence. The entire degeneration of microspore or pollen, or the complete failure of anther dehiscence can cause the complete failure of pollen dispersal. [ABSTRACT FROM AUTHOR]

Background: We summarize our experience of the diagnosis, surgical treatment, and prognosis of solid pseudopapillary tumors (SPTs). Methods: We carried out a retrospective study of clinical data from a series of 17 patients with SPT managed in two hospitals between October 2001 and November 2011. Results: All of the 17 patients were female and the average age at diagnosis was 26.6 years (range 11 years to 55 years). The tumor was located in the body or tail in ten patients, the head in five patients, and the neck in two patients. The median tumor size was 5.5 cm (range 2 cm to 10 cm). All 17 patients had curative resections, including seven distal pancreatectomies, five local resections, four pancreaticoduodenectomies, and one central pancreatectomy. Two patients required concomitant splenic vein resection due to local tumor invasion. All patients were alive and disease-free at a median follow-up of 48.2 months (range 2 to 90 months). There were no significant associations between clinicopathologic factors and malignant potential of SPT. Ki-67 was detected in three patients with pancreatic parenchyma invasion. Conclusions: The SPT is an infrequent tumor, typically affecting young women without notable symptoms. Surgical resection is justified even in the presence of local invasion or metastases, as patients demonstrate excellent long-term survival. Positive immunoreactivity for Ki-67 may predict the malignant potential of SPTs. [ABSTRACT FROM AUTHOR]

Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind lowyield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (whitepericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice. [ABSTRACT FROM AUTHOR]

The thin aluminum liners with an aspect ratio R/Δr≪1 have been imploded on the primary test stand (PTS) facility, where R is the outer radius of the liner and Δr is the thickness. The x-ray self-emission images present azimuthally correlated perturbations in the liner implosions. The experiments show that at −10 ns before the stagnation, the wavelengths of perturbation are about 0.93 mm and 1.67 mm for the small-radius and large-radius liners, respectively. We have utilized the resistive magnetohydrodynamic code PLUTO to study the development of magneto-Rayleigh–Taylor (MRT) instabilities under experimental conditions. The calculated perturbation amplitudes are consistent with the experimental observations very well. We have found that both mode coupling and long implosion distance are responsible for the more developed instabilities in the large-radius liner implosions. [ABSTRACT FROM AUTHOR]

Previous in vivo and in vitro studies have shown that human mesenchymal stem cells (MSCs) exhibit tropism for gliomas. However, the mechanism underlying this directed migration remains unclear. The aim of the present study was to investigate the possible mechanism underlying platelet-derived growth factor-BB (PDGF-BB)-induced chemotactic migration of bone marrow-derived MSCs (BMSCs) toward glioma. Rat glioma C6 cell-conditioned medium was utilized to evaluate the chemotactic response of BMSCs toward glioma using an in vitro migration assay. Recombinant rat PDGF-BB was added to C6 cell-conditioned medium to assess its effect on the tropism of BMSCs. The effect of PDGF-BB on the expression levels of cluster of differentiation (CD)44 in BMSCs was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence assays. The results revealed that chemotactic migration was induced in BMSCs by rat glioma C6 cell-conditioned medium, which was enhanced by PDGF-BB treatment in a dose-dependent manner. Furthermore, RT-PCR and immunofluorescence assays showed that CD44 expression was upregulated in BMSCs following treatment with 40 ng/ml PDGF-BB for 12 h. Additionally, 3-h pretreatment with the anti-CD44 neutralizing antibody OX-50 was observed to attenuate the tropism of BMSCs toward glioma in the presence or absence of PDGF-BB. The results of the present study indicate that CD44 mediates the tropism of BMSCs toward glioma, and PDGF-BB promotes the migration of BMSCs toward glioma via the upregulation of CD44 expression in BMSCs. These findings suggest CD44 inhibit ion may be a potent ial therapeut ic target for the treatment of glioma. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus ClfA adhesin is a protective antigen that induces partial immunity against S. aureus infection in mice. To identify the antigenic epitope of ClfA, a monoclonal antibody (mAb) D01 against the recombinant protein was produced by the hybridoma technique. The mAb was used to immunoscreen a random phage-displayed peptide library as the immunogen. After three rounds of biopanning, 41 positive clones were identified. Sixteen phage clones were sequenced and their amino acids were deduced. One mimotope (SKVGIDKRRGTA) showed good match with ClfA adhesin at 383-394 aa and the serum of mice induced by the phage clone clearly recognized ClfA adhesin. [ABSTRACT FROM AUTHOR]

It is well known that chemical functionalization of carbon nanotubes (CNTs) can offer an effective route to modify their properties, thus significantly widening their application areas. In the present work, through spin-polarized density functional theory (DFT) calculations, we have systemically studied the chemical functionalization of pyridine-like and porphyrin-like nitrogen-doped carbon (CN) nanotubes with 13 different transition metals (TMs = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pt, Pd, and Au). Particular attention is paid to searching for the most stable configurations, calculating the corresponding binding energies, and exploring the effects of the chemical functionalization of TMs on the electronic properties of the two CN nanotubes. We find that (1) due to the strong interaction between the d orbitals of TMs and the p orbitals of N atoms, the binding strengths of TMs with the two CN nanotubes are significantly enhanced when compared to the pure CNTs; (2) the electronic properties of CN nanotubes can be effectively modified in various ways, which are strongly dependent on the adsorbed TMs. [ABSTRACT FROM AUTHOR]

The P genome of Agropyron Gaertn., a wild relative of wheat, contains an abundance of desirable genes that can be utilized as genetic resources to improve wheat. In this study, wheat - Aegilops cylindrica Host gametocidal chromosome 2C addition lines were crossed with wheat - Agropyron cristatum (L.) Gaertn. disomic addition line accession II-21 with alien recombinant chromosome (1·4)P. We successfully induced wheat - A. cristatum alien chromosomal translocations for the first time. The frequency of translocation in the progeny was 3.75%, which was detected by molecular markers and genomic in situ hybridization (GISH). The translocation chromosomes were identified by dual-color GISH /fluorescence in situ hybridization (FISH). The P genomic DNA was used as probe to detect the (1·4)P chromosome fragment, and pHvG39, pAs1, or pSc119.2 repeated sequences were used as probes to identify wheat translocated chromosomes. The results showed that six types of translocations were identified in the three wheat - A. cristatum alien translocation lines, including the whole arm or terminal portion of a (1·4)P chromosome. The (1·4)P chromosome fragments were translocated to wheat chromosomes 1B, 2B, 5B, and 3D. The breakpoints were located at the centromeres of 1B and 2B, the pericentric locations of 5BS, and the terminals of 5BL and 3DS. In addition, we obtained 12 addition-deletion lines that contained alien A. cristatum chromosome (1·4)P in wheat background. All of these wheat - A. cristatum alien translocation lines and addition-deletion lines would be valuable for identifying A. cristatum chromosome (1·4)P-related genes and providing genetic resources and new germplasm accessions for the genetic improvement of wheat. The specific molecular markers of A. cristatum (1·4)P chromosome have been developed and used to track the (1·4)P chromatin. Le génome P de l’Agropyron Gaertn., une espèce sauvage apparentée au blé, contient plusieurs gènes d’intérêt et pourrait servir de ressource génétique pour améliorer le blé. Dans ce travail, des lignées d’addition blé-Aegilops cylindrica Host contenant le chromosome gamétocide 2C ont été croisées avec la lignée II-21, une lignée d’addition disomique blé-Agropyron cristatum (L.) Gaertn. qui contient un chromosome recombinant (1·4)P. Les auteurs ont réussi pour la première fois à induire des translocations blé-A. cristatum. La fréquence de translocations au sein de la progéniture était de 3,75 %, celles-ci étant détectées à l’aide de marqueurs moléculaires et d’hybridation génomique in situ (GISH). Les chromosomes impliqués dans ces translocations ont été identifiés par analyse GISH/FISH en deux couleurs. L’ADN du génome P a été employé comme sonde pour détecter le fragment du chromosome (1·4)P, tandis que les séquences répétées pHvG39, pAs1 ou pSc119,2 ont été utilisées comme sondes pour identifier les chromosomes du blé impliqués dans les translocations. Les fragments du chromosome (1·4)P ont été transportés sur les chromosomes 1B, 2B, 5B ou 3D. Les cassures étaient situées à l’endroit des centromères pour les chromosomes 1B et 2B, dans les régions péricentromériques chez 5BS et aux extrémités des chromosomes 5BL et 3DS. De plus, les auteurs ont obtenu douze lignées d’addition-délétion contenant le chromosome (1·4)P entier de l’A. cristatum chez le blé. Toutes ces lignées portant des translocations ou des additions-délétions blé-A. cristatum pourraient s’avérer utiles pour identifier des gènes portés sur le chromosome (1·4)P de l’A. cristatum. Elles constituent également des ressources génétiques et de nouvelles accessions pour l’amélioration génétique du blé. Des marqueurs moléculaires spécifiques du chromosome (1·4)P de l’A. cristatum ont été développés et seront utiles pour suivre la chromatine (1·4)P. Les résultats ont montré que six types de translocation ont été documentés au sein de trois lignées de translocation blé-A. cristatum, incluant un bras entier ou la portion terminale du chromosome (1·4)P. [ABSTRACT FROM AUTHOR]

Recently, ETHYLENE OVERPRODUCER 1 (ETO1) had been cloned and identified as a negative post-transcriptional regulator in the ethylene biosynthesis in Arabidopsis. However, little was known about the role of ETO1 in other species, especially in tomato, which was an ideal model for studying the biosynthesis of ethylene during tomato fruit ripening. In this study, a tomato ETHYLENE OVERPRODUCER 1-LIKE 1 (LeEOL1) was cloned. The LeEOL1 cDNA was 3,515 bp long and carried an ORF that putatively encoded a polypeptide of 886 amino acids with a predicted molecular mass of 95 kDa. It shared 74% identity in amino acid sequence with Arabidopsis EOL1 and had one BTB (Broad-complex, Tramtrack, Bric-à-brac) domain and two TPR (tetratricopeptide repeat) domains, which were also conserved domains in AtEOL1. RT-PCR analysis of the temporal expression of LeEOL1 showed that its transcript decreased companied with increase of ethylene production in tomato ripening. The level of LeEOL1 transcripts in wild type tomato fruit at mature green stage did not distinctively change when treated with exogenous ethylene. [ABSTRACT FROM AUTHOR]

Loss-of-function ethylene insensitive 2 (EIN2) mutations showed ethylene insensitivity in Arabidopsis, which indicated an essential role of EIN2 in ethylene signaling. However, the function of EIN2 in fruit ripening has not been investigated. To gain a better understanding of EIN2, the temporal regulation of LeEIN2 expression during tomato fruit development was analyzed. The expression of LeEIN2 was constant at different stages of fruit development, and was not regulated by ethylene. Moreover, LeEIN2-silenced tomato fruits were developed using a virus-induced gene silencing fruit system to study the role of LeEIN2 in tomato fruit ripening. Silenced fruits had a delay in fruit development and ripening, related to greatly descended expression of ethylene-related and ripening-related genes in comparison with those of control fruits. These results suggested LeEIN2 positively mediated ethylene signals during tomato development. In addition, there were fewer seeds and locules in the silenced fruit than those in the control fruit, like the phenotype of parthenocarpic tomato fruit. The content of auxin and the expression of auxin-regulated gene were declined in silenced fruit, which indicated that EIN2 might be important for crosstalk between ethylene and auxin hormones. (Managing editor: Li-Hui Zhao) [ABSTRACT FROM AUTHOR]

The article reports on the results of a study of the expression and DNA binding activity of tomato transcription factor ripening inhibitor (RIN) protein. A description of the experimental set-up and measurement methods is presented. The study concluded that an optimal expression and purification system was suitable for obtaining active RIN with DNA binding activity.

We propose a quantity called modulus fidelity to measure the closeness of two quantum pure states. We use it to investigate the closeness of eigenstates in one-dimensional hard-core bosons. When the system is integrable, eigenstates close to their neighbor or not, which leads to a large fluctuation in the distribution of modulus fidelity. When the system becomes chaos, the fluctuation is reduced dramatically, which indicates all eigenstates become close to each other. It is also found that two kind of closeness, i.e., closeness of eigenstates and closeness of eigenvalues, are not correlated at integrability but correlated at chaos. We also propose that the closeness of eigenstates is the underlying mechanism of eigenstate thermalization hypothesis (ETH) which explains the thermalization in quantum many-body systems. [ABSTRACT FROM AUTHOR]

We investigate the dependence of the average parameter estimation precision (APEP), which is defined by the quantum Fisher information, on the polar angle of the initial coherent spin state |θ0, φ0〉 in a one-axis twisting model. Jin et al. [New J. Phys.11 (2009) 073049] found that the spin squeezing sensitively depends on the polar angle θ0 of the initial coherent spin state. We show explicitly that the APEP is robust to the initial polar angle θ0 in the vicinity of π/2 and a near-Heisenberg limit ∝ 2/N in quantum single-parameter estimation may still be achieved for states created with the nonlinear evolution of the nonideal coherent spin states θ0 ∼ π/2. Based on this model, we also consider the effects of the collective dephasing on spin squeezing and the APEP. [ABSTRACT FROM AUTHOR]