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To elucidate the molecular pathology underlying the deve- lopment of hepatocellular carcinoma (HCC), we used 41 highly polymorphic microsatellite markers to examine 55 HCC and cor- responding non-tumor liver tissues on chromosome 9, 16 and 17.
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Chinese white poplar (Populus tomentosa Carr.) is an indigenous tree species in China which plays a key role in the establishment of plantation forests and the conversion of cropland to forestland. By using response surface method...
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Chinese white poplar (Populus tomentosa Carr.) is an indigenous tree species in China which plays a key role in the establishment of plantation forests and the conversion of cropland to forestland. By using response surface methodology based on rotatable central composite design, we conducted a test with clone 87 of P. tomentosa seedlings to quantify the interactions among soil water content (W), nitrogen application (N), and phosphorus application (P) on plant stem height (SH), leaf area (LA), net photosynthetic rate (P N) and biomass yield (BY). Our results showed that W, N and P had obvious positive effects on plant SH, LA, P N and BY, and the magnitude of effects in decreasing order was Wa??>a??Na??>a??P. There were synergistic effects of Wa????a??N on SH, LA and BY, whose values first increased and then decreased with N increasing under a fixed level of W and also with W increasing under a fixed N. A similar trend was found with the interaction of Wa????a??P significantly effecting LA. A multiple target decision model synthesizing all four parameters was established to obtain the optimized combination. We concluded that the recommended combination of W, N and P for growers was Wa??=a??78.1% of the field capacity, Na??=a??4.48a??ga??planta??1, and Pa??=a??1.67a??ga??planta??1. These recommendations should help to achieve maximum growth potential of P. tomentosa seedlings, obtain high water and fertilizer use efficiencies and reduce the risk of nitrate pollution of groundwater in arid and semi-arid regions.View full textDownload full textKeywordsbiomass yield, Chinese white poplar (Populus tomentosa Carr.), rotatable central composite design, nitrogen and phosphorus application, soil water.Related var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/00380768.2010.549445
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Macrocycles made of cholate building blocks were
previously found to transport glucose readily across lipid bilayers. In
this study, an 15N, 13Cα-labeled glycine was inserted into a cyclic cholate
trimer and attached at the end o...
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Macrocycles made of cholate building blocks were
previously found to transport glucose readily across lipid bilayers. In
this study, an 15N, 13Cα-labeled glycine was inserted into a cyclic cholate
trimer and attached at the end of a linear trimer, respectively. The
isotopic labeling allowed us to use solid-state NMR spectroscopy to study
the dynamics, aggregation, and depth of insertion of these compounds in
lipid membranes. The cyclic compound was found to be mostly
immobilized in DLPC, POPC/POPG, and POPC/POPG/cholesterol
membranes, whereas the linear trimer displayed large-amplitude motion
that depended on the membrane thickness and viscosity. 13C-detected 1H
spin diffusion experiments revealed the depth of insertion of the compounds in the membranes, as well as their contact with
water molecules. The data support a consistent stacking model for the cholate macrocycles in lipid membranes, driven by the
hydrophobic interactions of the water molecules in the interior of the macrocycles. The study also shows a strong preference of
the linear trimer for the membrane surface, consistent with its lack of transport activity in earlier liposome leakage assays.
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Pyrrolidine-catalyzed domino Michael-aldol reaction of alpha,beta-unsaturated trifluoromethyl ketones and ketones was achieved under mild conditions; beta-hydroxy-beta-trifluoromethyl cyclohex-anones were obtained in high yields w...
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Pyrrolidine-catalyzed domino Michael-aldol reaction of alpha,beta-unsaturated trifluoromethyl ketones and ketones was achieved under mild conditions; beta-hydroxy-beta-trifluoromethyl cyclohex-anones were obtained in high yields with good diastereoselectivi-ties.The importance of fluorine-containing compounds in the fields of agricultural, medicinal and material chemistry is well known.1 Among various organofluorine compounds, a-trifluoromethyl tertiary alcohols have attracted much attention recently because they could serve as liquid crystals23 and drugs such as Efavirenz (anti-HIV). On the other hand, since cyclic compounds form the backbone of many bioactive compounds, the development of synthetic methods for cyclic a-trifluoromethyl tertiary alcohols would be very valuable in the field of pharmaceutical research.
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A numerical method based on the uniform and hexahedral grids generated from computational fluid dynamics is presented for the analysis of aero-optical performance. A single grid is taken as a cell with isotropy and homogeneity ins...
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A numerical method based on the uniform and hexahedral grids generated from computational fluid dynamics is presented for the analysis of aero-optical performance. A single grid is taken as a cell with isotropy and homogeneity inside, and it is assumed that the light rays transmit grid by grid. Ray tracing is employed to track the transmission through the flow of supersonic fluids, and a recursive algorithm is derived. The line-of-sight errors and optical path differences produced by the mean density fields were calculated, the phase variances brought from the density fluctuations were computed, and the Strehl ratios were figured out. This method potentially provides a solution for the prediction of aero-optical effects.
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Mobile genetic elements have impacted biological evolution across all studied organisms, but evidence for a role in evolutionary emergence of an entire phylogenetic clade has not been forthcoming. We suggest that mobile element pr...
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Mobile genetic elements have impacted biological evolution across all studied organisms, but evidence for a role in evolutionary emergence of an entire phylogenetic clade has not been forthcoming. We suggest that mobile element predation played a formative role in emergence of the phytoplasma clade. Phytoplasmas are cell wall-less bacteria that cause numerous diseases in plants. Phylogenetic analyses indicate that these transkingdom parasites descended from Gram-positive walled bacteria, but events giving rise to the first phytoplasma have remained unknown. Previously we discovered a unique feature of phytoplasmal genome architecture, genes clustered in sequence-variable mosaics (SVMs), and suggested that such structures formed through recurrent, targeted attacks by mobile elements. In the present study, we discovered that cryptic prophage remnants, originating from phages in the order Caudovirales, formed SVMs and comprised exceptionally large percentages of the chromosomes of 'Candidatus Phytoplasma asteris'-related strains OYM and AYWB, occupying nearly all major nonsyntenic sections, and accounting for most of the size difference between the two genomes. The clustered phage remnants formed genomic islands exhibiting distinct DNA physical signatures, such as dinucleotide relative abundance and codon position GC values. Phytoplasma strain-specific genes identified as phage morons were located in hypervariable regions within individual SVMs, indicating that prophage remnants played important roles in generating phytoplasma genetic diversity. Because no SVM-like structures could be identified in genomes of ancestral relatives including Acholeplasma spp., we hypothesize that ancient phage attacks leading to SVM formation occurred after divergence of phytoplasmas from acholeplasmas, triggering evolution of the phytoplasma clade.
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Light-activated therapies can be used to eradicate diseased cells and tissues in a non-invasive manner. Much attention has been focused on the emerging potential of photothermolysis (also referred to as optical hyperthermia), whic...
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Light-activated therapies can be used to eradicate diseased cells and tissues in a non-invasive manner. Much attention has been focused on the emerging potential of photothermolysis (also referred to as optical hyperthermia), which involves the conversion of absorbed light into heat via nonradiative mechanisms. Photoactivated effects can be localized and intensified by employing exogenous agents with large absorption cross-sections, confining damage to areas of interest with minimal collateral effects.'1' In particular, targeted photothermolysis may be most effective when mediated by photothermal agents that absorb strongly at near-infrared (NIR) frequencies, to enable deeper penetration into biological tissues.
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AIM To study the inhibitory effects of VES (RRR-α-tocopheryl Succinate, VES), a derivative of natural Vitamin E, on benzo (a) pyrene (B(a)P)-induced forestomach tumor in female mice. METHODS The model of B (a) P-induced Forestoma...
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AIM To study the inhibitory effects of VES (RRR-α-tocopheryl Succinate, VES), a derivative of natural Vitamin E, on benzo (a) pyrene (B(a)P)-induced forestomach tumor in female mice. METHODS The model of B (a) P-induced Forestomach tumor was established according to The methods of Wattenberg with slight Modifications. One hundred and eightly female Mice (6 weeks old) were divided into six groups Equally; negative control (Succinic acid), Vehicle control (Succinate + B(a)P), positive Control (B(a)P), high VES (2.5 g/kg.b.w+B(a) P), low VES(1.25 g/kg. B. W +B (a) P) ig as well As VES by ip (20 mg/kg. B. W + B (a) P). Except The negative control group, the mice were Administrated with B(a)P ig.
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Solution-processed organic semiconductors to replace amor-phous silicon as the active layer in field-effect transistors (FETs) have attracted great attention due to their potential applications in flexible and low-cost E-paper, sm...
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Solution-processed organic semiconductors to replace amor-phous silicon as the active layer in field-effect transistors (FETs) have attracted great attention due to their potential applications in flexible and low-cost E-paper, smart card, radio frequency identification, and displays.[1] Recently, significant progress has been made in the performance of solution-processed FETs based on both single-crystalline (5-30 cm~2 V~(-1) s~(-1))[2] and thin-film (2-3 cm~2 V~(-1) s~(-1))[3] of organic small-molecule semiconductors. However, the thin-film uniformity of the small molecules usually varies from area to area due to their high crystalline properties, thus limiting their large-scale applications.
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A general method for sequence-specific binding of peptides remains elusive despite decades of research. By creating an array of "hydrophobically coded dimples" on the surface of surface—core doubly cross-linked micelles, we synth...
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A general method for sequence-specific binding of peptides remains elusive despite decades of research. By creating an array of "hydrophobically coded dimples" on the surface of surface—core doubly cross-linked micelles, we synthesized water-soluble nanoparticle receptors to recognize peptides by the location, number, and nature of their hydrophobic side chains. Minute differences in the side chains could be distinguished, and affinities up to 20 nM were obtained for biologically active oligopeptides in water.
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