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Interleukin (IL)-13-associated signal pathway plays an important role in schistosomiasis hepatic fibrosis. In this study we tried to investigate the effects of corilagin to ameliorate schistosomiasis hepatic fibrosis through regulating IL-13-associated signal pathway in vitro and in vivo. Cellular model was set up with hepatic stellate cells-T6 cells stimulated by rIL-13 and male Balb/c mice were infected with Schistosoma japonicum cercariaeas as animal model. Liver histological changes were observed with haematoxylin and eosin staining. Masson staining was employed to observe the change of egg granulomas. Expression of Col (collagen) and Col III were examined with Immunohistochemistry. Western bolt was employed to detect the JAK-1 and IL13Rα1 proteins. The mRNA expression of Col I, Col III, IL-13, JAK-1 and IL13Rα1 were tested by quantitative polymerase chain reaction. As a result, less inflammatory changes were found in all corilagin groups compared with model group and praziquantel group. The mRNA levels of Col I, Col III, IL-13, JAK-1 and IL13Rα1 were significantly decreased after corilagin intervention (P < 0·01). JAK-1 and IL-13Rα1 protein levels were also greatly decreased in the corilagin groups (P < 0·01). In conclusion, corilagin could ameliorate schistosomiasis hepatic fibrosis by down-regulating the expression of IL-13 and signal molecules in IL-13 pathway.
High-resolution SIMS U–Pb dating of metamorphic zircons of the TTG gneisses, gneissic granitoid and amphibolites of the Lushan terrane, Taihua metamorphic complex, suggests that the metamorphism had taken place at least as early as ~1.96–1.86 Ga. These new dates, along with reference data, demonstrate that the southern and middle terranes of the Trans-North China Orogen had been involved in the continent–continent collision between the Western Block and the Eastern Block of the North China Craton. This orogenic process started as early as 1.96 Ga and lasted as late as 1.80 Ga.
The three-dimensional instabilities of axisymmetric flow are investigated in a laterally heated vertical cylinder by linear stability analysis. Heating is confined to a central zone on the sidewall of the cylinder, while other parts of the sidewall are insulated and both ends of the cylinder are cooled. The length of the heated zone equals the radius of the cylinder. For three different aspect ratios,
$A= 1.92 $
, 2, 2.1 (
/radius), the dependence of the critical Rayleigh number on the Prandtl number (from 0.02 to 6.7) has been studied in detail. For such a kind of laterally heated convection, some interesting stability results are obtained. A monotonous instability curve is obtained for
$A= 1.92 $
, while the instability curves for
$A= 2 $
$A= 2.1 $
are non-monotonous and multivalued. In particular, an instability island has been found for
. Moreover, mechanisms corresponding to different instability results are obtained when the Prandtl number changes. At small Prandtl number, the flow is oscillatory unstable, which is dominated by hydrodynamic instability. At intermediate Prandtl number, the interaction between buoyancy and shear in the base flow plays a more important role than pure hydrodynamic instability. At even higher Prandtl number, Rayleigh–Bénard instability becomes the dominant process and the flow loses stability through steady bifurcation.
In this work, the metallic element Ru is introduced into a-Si:H. The structural and electrical properties of the films doped with Ru have been investigated. Raman spectra reveal that the addition of Ru disarranges further the intrinsically disordered amorphous network and generates more coordinated defects. Meanwhile, a new paramagnetic signal, associated with the holes localized in valence band tail, has been observed. Moreover, the conductivity increases by about nine orders of magnitude with the increase of doping concentration, and the temperature coefficient of resistance (TCR) results show that this material may have a potential application in the infrared detectors.
A joint diagnostic system was established for the diagnosis of laser-driven shock wave experiments. The system has high temporal resolution (time resolution ~12 ps) and high spatial resolution (spatial resolution ~7 μm) and fits for diagnostics of the experiment with small sample size and short time physical process. The joint diagnostic system was applied for shock wave measurement on the Shenguang-II laser facility. The passive shock breakout signal and active diagnostic signal were simultaneously obtained. The temporal measurement reliability of the system was verified using a multi-layered target. The experimental results show that the two measurement results were consistent.
Amphibolites and metapelites exposed in the Zanhuang metamorphic complex situated in the south-middle section of the Trans-North China Orogen (TNCO) underwent upper-amphibolite-facies metamorphism and record clockwise P–T paths including retrograde isothermal decompression. High-resolution zircon U–Pb geochronological analyses indicate that the metamorphic peak occurred during ~ 1840–1860 Ma, which is in accordance with the ubiquitous metamorphic ages of ~ 1850 Ma retrieved by miscellaneous geochronologic methods throughout the metamorphic terranes of the northern TNCO, confirming that the south-middle section of the TNCO was involved in the amalgamation of the Eastern and Western Blocks of the North China Craton during the Palaeoproterozoic.
During directional solidification of Cu–Ge peritectic alloys, a two-phase separated structure has been observed. With proper growth conditions, the peritectic ζ-Cu5Ge and primary α-Cu phases completely separate and form cylindrical layered structures. It is found that the formation of the separated structure is closely related to double diffusive convection and growth conditions. In the two-phase separated structure, a large trijunction region of peritectic reaction forms around the cylindrical α-Cu phase. During peritectic reaction, the morphological instabilities of ζ-Cu5Ge occur under high pulling velocities and are explained by the constitutional undercooling criterion. A new coupling growth between the ζ-Cu5Ge-phase and the groove of α-Cu phase near the trijunction is observed. Different from peritectic coupling growth, the diffusion coupling is established below the peritectic temperature. This two-phase separated growth process creates new opportunities for the fabrication of functionally layered materials.
The effects of hydrogen on the structure of Zr-based bulk metallic glasses were investigated by positron annihilation lifetime spectroscopy. Three lifetime components are identified, indicating the presence of three distinct size ranges for open volume defects in the glass. The concentration of the smallest sites identified as tetrahedral interstitial holes in the densely packed and the intermediate sites identified as flow defects, changes with hydrogen addition. The concentration of tetrahedral interstitial holes in Zr55Cu30Ni5Al10 alloys initially increases with the increase of hydrogen content. When Zr55Cu30Ni5Al10 alloys were prepared in Ar + 10%H2 atmospheres, the concentration of tetrahedral interstitial holes reaches a maximum, which may provide a more dense random-packed structure. For Zr57Al10Cu15.4Ni12.6Nb5alloys, the increase of hydrogen content causes a decrease in the concentration of tetrahedral interstitial holes and an increase in the concentration of flow defects.
Electron tomography and high-resolution transmission electron microscopy were used to characterize the unique 3-dimensional (3D) structures of twinned Zn3P2 (tetragonal) and InAs (zinc blende) nanowires synthesized by the vapor transport method. The Zn3P2 nanowires adopt a unique superlattice structure that consists of twinned octahedral slice segments having alternating orientations along the axial  direction of a pseudocubic unit cell. The apices of the octahedral slice segment are indexed as six equivalent <112> directions at the  zone axis. At each 30 degrees turn, the straight and zigzagged morphologies appear repeatedly at the <112> and <011> zone axes, respectively. The 3D structure of the twinned Zn3P2 nanowires is virtually the same as that of the twinned InAs nanowires. In addition, we analyzed the 3D structure of zigzagged CdO (rock salt) nanowires and found that they include hexahedral segments, whose six apices are matched to the <011> directions, linked along the  axial direction. We also analyzed the unique 3D structure of rutile TiO2 (tetragonal) nanobelts; at each 90 degree turn, the straight morphology appears repeatedly, while the in-between twisted form appears at the  zone axis. We suggest that the TiO2 nanobelts consist of twinned octahedral slices whose six apices are indexed by the <011>/<001> directions with the axial  direction.
Recent work (Baskin & Laor 2004; Dong et al. 2009a, b) suggests that the Eddington ratio (l ≡ L/LEdd) is the origin of all the significant first-order object-to-object variations of quasar spectral properties from the zeroth-order similarity of AGN spectra; specifically, this includes the PC1 of Boroson & Green (1992), the classic or inverse Baldwin effect (Baldwin 1977), and even blueshifting (i.e., blue asymmetry) of high-ionization emission lines (Dong et al. 2009c).
The outcome of Plasmodium yoelii 17XL-infected BALB/c and DBA/2 mice, ranging from death to spontaneous cure, respectively, depends largely on the establishment of effective pro-inflammatory type 1 responses during the early stages of infection and associates with CD4+CD25+Foxp3+regulatory T cells (Tregs). Here, effects of Tregs were analysed on early P. yoelii 17XL infection in BALB/c and DBA/2 mice. In vivo depletion of Tregs significantly reversed the inhibited establishment of effective pro-inflammatory type 1 responses in BALB/c mice, indicating that this cell population contributed to the suppression of T-cell function in malaria. Moreover, the proportion and absolute numbers of IL-10-secreting Tregs in BALB/c mice were significantly higher than that found in DBA/2 mice by intracytoplasmic staining, and IL-10 production was correlated with the Tregs population. In addition, in vivo Tregs depletion decreased the production of IL-10 and the apoptosis of CD4+ T cells. Consistently, IL-10R blockade also had the same effect as that of Tregs depletion in P. yoelii 17XL-infected BALB/c mice. Our data demonstrate that Tregs perhaps have an important role in regulating pro-inflammatory type 1 responses in an IL-10-dependent manner and induce CD4+ T cell apoptosis during the early stage of P. yoelii 17XL infection.
Epidermal growth factor receptor (EGFR) is becoming a perfect target for killing carcinoma cells, especially because of its overexpression on the surface of these cells. Cationic antimicrobial peptides (CAP) have their own special mechanism of membrane-lytic cytotoxicity. In this study, a membrane-lytic immunotoxin (IT), chimeric protein MEGFMEL, was constructed to kill carcinoma cells with EGFR overexpression. This protein is composed of mouse (Mus musculus) epidermal growth factor (MEGF), as the target part, and melittin (MEL), as the cytotoxic part. Using Escherichia coli BL21 and pET30a as expression strain and vector, respectively, 63.45 μg/ml of MEGFMEL (68% purity) was obtained through low-temperature induction of expression and a thawing-freezing purification procedure (without cytolysis). In vitro activity measurement showed that this MEGFMEL significantly induced a lethal effect on A431 carcinoma cells overexpressing EGFR on the surface, with an LD50 value 52.6 μg/ml. The results suggest that the use of CAP as the toxin in the construction of unique membrane-lytic ITs aimed at EGFR is feasible.
The objective of the current study was to evaluate the effects of calcium propionate supplementation on rumen fermentation, urinary excretion of purine derivatives (PD) and feed digestibility in the total gastrointestinal tract of steers. Eight ruminally cannulated Simmental steers (462±14 kg) were used in a replicated 4×4 Latin square arrangement of treatments with experimental periods of 21 days. The treatments were: control (without calcium propionate), LCaP (calcium propionate – low), MCaP (calcium propionate – medium) and HCaP (calcium propionate – high) with 100, 200 and 300 g calcium propionate per steer per day. Diet consisted of 0·60 maize stover and 0·40 concentrate (dry matter (DM) basis). DM intake (average 9 kg/day) was restricted to a maximum of 0·90 of ad libitum intake. Ruminal pH (range of 6·7–6·5) linearly (P<0·003) and quadratically (P<0·005) decreased, and total volatile fatty acid (VFA) concentration (range of 64·4–67·1 mm) tended (P<0·087) to increase linearly with rising calcium propionate supplementation. Ratio of acetate to propionate fell linearly (P<0·006) and quadratically (P<0·008) from 3·5 to 2·6 as calcium propionate supplementation increased due to the additional propionate supplementation. In situ ruminal neutral detergent fibre (NDF) degradation of maize stover and crude protein (CP) degradability of concentrate mix were improved with increasing concentration of calcium propionate. Urinary excretion of PD was linearly (P<0·032) and quadratically (P<0·048) increased with greater calcium propionate supplementation (72, 74, 77 and 76 mmol/day for control, LCaP, MCaP and HCaP, respectively). Similarly, digestibilities of organic matter (OM), NDF and CP in the total tract were also linearly and quadratically improved with increasing calcium propionate. The results indicate that the calcium propionate supplementation potentially improves rumen fermentation and feed digestion in beef cattle. It is speculated that calcium propionate stimulates the digestive microorganisms or enzymes in a dose-dependent manner. In the experimental conditions of the current trial, the optimum calcium propionate dose was about 200 g calcium propionate per steer per day.
The bone morphogenetic protein receptor IB (BMPR-IB) gene, which controls the fecundity of Booroola Merino ewes, was studied as a candidate gene for the prolificacy of Small Tail Han and Hu ewes. A single nucleotide polymorphism of the BMPR-IB gene was detected in both high (Small Tail Han and Hu) and low (Suffolk and Dorset) fecundity sheep breeds by polymerase chain reaction–single-strand conformation polymorphism (PCR-SSCP) analysis. The results indicated the presence of the same mutation (A746G) of the BMPR-IB gene in both Small Tail Han and Hu ewes and in Booroola Merino ewes, but not in both Suffolk and Dorset ewes. In Small Tail Han ewes, frequencies of BB, B+ and ++ genotypes were 0.524, 0.383 and 0.093, respectively. In Hu ewes, these frequencies were 0.882, 0.118 and 0.000. The BMPR-IB genotype distributions were significantly different (P<0.001) among high- and low-fecundity sheep breeds. Small Tail Han ewes with genotype BB had 0.92 (P<0.01) and 1.02 (P<0.01) lambs more than those with genotype ++ in the first and second parity, respectively. These results demonstrated that the BMPR-IB gene is a major gene affecting the prolificacy in both Small Tail Han and Hu ewes, and could be used as a molecular genetic marker to select the litter size in sheep.
Analysis of mating type can provide an evaluation of the population genetic diversity of the rice blast fungus, Magnaporthe grisea. According to the sequences of MAT1-1 and MAT1-2 genes of the fungus, two pairs of PCR primers specific to the MAT1-1 and MAT1-2 alleles were designed, and the PCR thermal profile was also optimized. To confirm its application in mating type assessment, 10 tester isolates were tested by PCR. The PCR amplification pattern of these tester isolates corresponded to their known mating type. Furthermore, 150 rice-field isolates from Fujian Province were mated with tester isolates GUY11 and KA3 side by side and also tested by PCR. Results showed that 95.1% of 123 fertile isolates were the same in mating type as determined by both PCR-amplified allele-specific fragments and mating with GUY11/KA3. Among 27 sterile isolates determined by GUY11 and KA3, seven were MAT1-1 and 20 were MAT1-2 as determined by PCR. This study indicates that PCR is applicable in assessing M. grisea mating type and especially is capable of predicting the potential mating type of sterile isolates in the natural population of the fungus.
A cDNA library was constructed from the heading leaf in the early phase of the heading stage of Chinese cabbage (Brassica rapa L. ssp. pekinensis). By sequencing the randomly selected clones, 1363 sequences longer than 200 bp were found, with better trace data. After removing the poly(A) and contamination sequences, 1162 ESTs longer than 150 bp were obtained, of which 1102 shared significant similarity with known sequences in protein and nucleotide databases of the National Center for Biotechnology Information (NCBI) as revealed by searches using the BLASTX and BLASTN engines. Functional assignment of the ESTs was based on the method used in the Arabidopsis thaliana genome-sequencing project. About 77% of the putative protein sequences with known biological functions best matched with those of A. thaliana deposited in the non-redundant database of NCBI. These data suggest that Chinese cabbage is closely related to A. thaliana. This result is different from that reported in other Brassica species. At nucleotide level, however, 51% of the ESTs were homologous to those deposited for A. thaliana when all ESTs were searched against the est-others database. In addition, 60 ESTs had no homology with any of the plant gene sequences deposited in GenBank. These ESTs are very important for understanding the unique developmental process of Chinesecabbage and elaborating its genetic mapping. Among the genes with assigned functions, the most abundant representatives were those involved in protein synthesis and energy metabolism. With the 1162 ESTs, 895 non-redundant contigs were generated after being aligned using the Seqman II module of DNAStar software at the threshold of more than 80% homology over a minimum of 40 base pairs. Of these, 723 were singletons containing only one EST sequence, indicating that many kinds of such genes are expressed in the heading leaf of Chinese cabbage. An expression profile of Chinese cabbage heading leaf with the 1162 ESTs was therefore acquired in this work. This could be very useful for uncovering the mechanism of the heading process, which is the most obvious characteristic of Chinese cabbage and perhaps other related species, such as Brassica oleracea. This work could accelerate the finding and characterization of genes specifically expressed in the heading stage of Chinese cabbage.
Sterile mycelia isolated from Pinus tabulaeformis were grouped into white morphotype strains based on cultural characteristics. Eighteen of the isolates were randomly selected and identified to various taxonomic levels based on nuclear ribosomal DNA (nrDNA) sequence analysis. The 5.8S gene and flanking internal transcribed spacer (ITS1 and ITS2) regions of nrDNA were amplified and sequenced. Phylogenetic analysis of the 5.8S gene sequences indicated that the white morphotype strains were Ascomycota. Further identification was achieved by means of sequence similarity comparison and phylogenetic analysis of the ITS regions. Results showed that strains WMS9 and WMS10 were Lophodermium species (Rhytismataceae), while strains WMS11, WMS13 and WMS18 were species of Rhytismataceae. Strains WMS2, WMS3, WMS4, WMS5 and WMS6 were identified to Rosellinia, strain WMS1 to Entoleuca, and strain WMS14 to Nemania (Xylariaceae). Strains WMS7, WMS8, WMS12, WMS15, WMS16 and WMS17 were xylariaceous species. The potential of using DNA sequence analysis in the identification of endophytic fungi is discussed.
By the new method of Sm—Nd isotopic dating on phosphatic small skeletal fossils and collo-phanite minerals, the Zhongyicun Member of the earliest Cambrian Meishucun Stage at Meishucun in Yunnan, southern China, has been dated at 562.8 ± 7.9 Ma and 562.1 ± 5.7 Ma. Another Sm—Nd age, 570.3 ± 17.1 Ma, has been obtained with samples from the Zhongyicun Member in Yunnan and its stratigraphic equivalents in Sichuan and Xinjiang. These data tend to suggest that the best age estimate of the Precambrian—Cambrian boundary is very likely within the range of 560–570 Ma. As biophosphates and sedimentary phosphates are widely distributed in sequences of the Precambrian—Cambrian transition, the Sm-Nd isotopic method is recommended as an effective approach for precise dating of the initial Cambrian boundary.
Radar, aerial netting and ground sampling were used to study the autumn migration of Nilaparvata lugens (Stål) in Jiangsu Province in east central China. Emigration of macropterous adults increased from late August until late September as the main rice crop matured and was harvested. In early and mid September, the resulting windborne migrations carried the planthoppers mainly towards the west, although the migration directions ranged (within the western sector) from south to north. By late September, however, displacements were predominantly to the south-west on the then prevailing north-east monsoon winds: migration was particularly rapid when the north-easterlies were reinforced by typhoons. Although in late September such movements to more southerly latitudes are essential for the survival of the planthoppers' progeny, we found no definite evidence for preferential emigration on winds blowing towards the south. There were, however, indications that when winds towards the north occurred, the duration of migratory flight was curtailed. Irrespective of any possible preference for migration on northerlies, a large proportion of the N. lugens population would normally be carried in an adaptive southwards direction, because the advent of the north-east monsoon occurs at a time when the number of flight-ready planthoppers approaches its peak.
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