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271.
Hard carbon as a typical anode material for sodium ion batteries has received much attention in terms of its low cost and renewability. Herein, phosphorus‐functionalized hard carbon with a specific “honeycomb briquette” shaped morphology is synthesized via electrospinning technology. When applied as an anode material for Na+ storage, it exhibits an impressively high reversible capacity of 393.4 mA h g?1 with the capacity retention up to 98.2% after 100 cycles. According to first‐principle calculation, the ultrahigh capacity of the as‐prepared anode is ascribed to the enhancement of Na‐absorption through formation of P?O and P? C bonds in graphitic layers when doped with phosphorus. Moreover, the increase of electron density around the Fermi level is found to be mainly caused by O atoms instead of P atoms.  相似文献   
272.
Mutants of Clostridium butyricum E5 exhibiting resistance to allyl alcohol which produced the same quantities of 1,3-propanediol as the wild-type strain but more acetate than butyrate were isolated. The acetate-butyrate formation plays a major function in the regulation of the internal redox balance. Allyl alcohol resistance can be attributed not to the loss of 1,3-propanediol dehydrogenase but to a shift in the reductive properties of the enzyme. The data support the view that cellular regulation is modified to avoid intracellular accumulation of 3-hydroxypropionaldehyde.  相似文献   
273.
Using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), simple sequence repeats (SSR), and morphological traits, the first genetic maps for Cucurbita pepo (2n=2x=40) were constructed and compared. The two mapping populations consisted of 92 F2 individuals each. One map was developed from a cross between an oil-seed pumpkin breeding line and a zucchini accession, into which genes for resistance to Zucchini Yellow Mosaic Virus (ZYMV) from a related species, C. moschata, had been introgressed. The other map was developed from a cross between an oil-seed pumpkin and a crookneck variety. A total of 332 and 323 markers were mapped in the two populations. Markers were distributed in each map over 21 linkage groups and covered an average of 2,200 cM of the C. pepo genome. The two maps had 62 loci in common, which enabled identification of 14 homologous linkage groups. Polyacrylamide gel analyses allowed detection of a high number of markers suitable for mapping, 10% of which were co-dominant RAPD loci. In the Pumpkin-Zucchini population, bulked segregant analysis (BSA) identified seven markers less than 7 cM distant from the locus n, affecting lignification of the seed coat. One of these markers, linked to the recessive hull-less allele (AW11-420), was also found in the Pumpkin-Crookneck population, 4 cM from n. In the Pumpkin-Zucchini population, 24 RAPD markers, previously introduced into C. pepo from C. moschata, were mapped in two linkage groups (13 and 11 markers in LGpz1 and LGpz2, respectively), together with two sequence characterized amplified region (SCAR) markers linked to genes for resistance to ZYMV.  相似文献   
274.
Serine proteases in the nervous system have functional roles in neural plasticity. Among them, urokinase-type plasminogen activator (uPA) exerts a variety of functions during development, and is involved in learning and memory. Furthermore, psychostimulants strongly induce uPA expression in the mesolimbic dopaminergic pathway. In this study, doxycycline-regulatable lentiviruses expressing either uPA, a dominant-negative form of uPA, or non-regulatable lentiviruses expressing small interfering RNAs (siRNAs) targeted against uPA have been prepared and injected into the ventral tegmental area (VTA) of rat brains. Over-expression of uPA in the VTA induces doxycycline-dependent expression of its receptor, uPAR, but not its inhibitor, plasminogen activator inhibitor-1 (PAI-1). uPAR expression in the VTA is repressed upon silencing of uPA with lentiviruses expressing siRNAs. In addition, over-expression of uPA in the VTA promotes a 15-fold increase in locomotion activity upon cocaine delivery. Animals expressing the dominant-negative form of uPA did not display such hyperlocomotor activity. These cocaine-induced behavioural changes, associated with uPA expression, could be suppressed in the presence of doxycycline or uPA-specific siRNAs expressing lentiviruses. These data strongly support the major role of urokinase in cocaine-mediated plasticity changes.  相似文献   
275.
Cytoplasmic processing bodies are sites where nontranslating mRNAs accumulate for different fates, including decapping and degradation, storage, or returning to translation. Previous work has also shown that the Lsm1-7p complex, Dhh1p, and Pat1p, which are all components of P bodies, are required for translation and subsequent recruitment to replication of the plant virus brome mosaic virus (BMV) genomic RNAs when replication is reproduced in yeast cells. To better understand the role of P bodies in BMV replication, we examined the subcellular locations of BMV RNAs in yeast cells. We observed that BMV genomic RNA2 and RNA3 accumulated in P bodies in a manner dependent on cis-acting RNA replication signals, which also directed nonviral RNAs to P bodies. Furthermore, the viral RNA-dependent RNA polymerase coimmunoprecipitates and shows partial colocalization with the P-body component Lsm1p. These observations suggest that the accumulation of BMV RNAs in P bodies may be an important step in RNA replication complex assembly for BMV, and possibly for other positive-strand RNA viruses.  相似文献   
276.
Genomic selection (GS) is a modern breeding approach where genome-wide single-nucleotide polymorphism (SNP) marker profiles are simultaneously used to estimate performance of untested genotypes. In this study, the potential of genomic selection methods to predict testcross performance for hybrid canola breeding was applied for various agronomic traits based on genome-wide marker profiles. A total of 475 genetically diverse spring-type canola pollinator lines were genotyped at 24,403 single-copy, genome-wide SNP loci. In parallel, the 950 F1 testcross combinations between the pollinators and two representative testers were evaluated for a number of important agronomic traits including seedling emergence, days to flowering, lodging, oil yield and seed yield along with essential seed quality characters including seed oil content and seed glucosinolate content. A ridge-regression best linear unbiased prediction (RR-BLUP) model was applied in combination with 500 cross-validations for each trait to predict testcross performance, both across the whole population as well as within individual subpopulations or clusters, based solely on SNP profiles. Subpopulations were determined using multidimensional scaling and K-means clustering. Genomic prediction accuracy across the whole population was highest for seed oil content (0.81) followed by oil yield (0.75) and lowest for seedling emergence (0.29). For seed yieId, seed glucosinolate, lodging resistance and days to onset of flowering (DTF), prediction accuracies were 0.45, 0.61, 0.39 and 0.56, respectively. Prediction accuracies could be increased for some traits by treating subpopulations separately; a strategy which only led to moderate improvements for some traits with low heritability, like seedling emergence. No useful or consistent increase in accuracy was obtained by inclusion of a population substructure covariate in the model. Testcross performance prediction using genome-wide SNP markers shows considerable potential for pre-selection of promising hybrid combinations prior to resource-intensive field testing over multiple locations and years.  相似文献   
277.
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279.
There is an increased interest from the vaccine industry to use mammalian cell cultures for influenza vaccine manufacturing. Therefore, it became important to study the influenza infection mechanism, the viral–host interaction, and the replication kinetics from a bioprocessing stand point to maximize the influenza viral production yield in cell culture. In the present work, influenza replication kinetics was studied in HEK293 cells. Two infection conditions were evaluated, a low (0.01) and a high multiplicity of infection (1.0). Critical time points of the viral production cycle (infection, protein synthesis, viral assembly and budding, viral release, and host‐cell death) were identified in small‐scale cell cultures. Additionally, cell growth, viability, and viral titers were monitored in the viral production process. The infection state of the cultivated cell population was assessed by influenza immunolabeling throughout the culture period. Influenza virus production kinetics were also on‐line monitored by dielectric spectroscopy and successfully correlated to real‐time capacitance measures. Overall, this work provided insights into the mechanisms associated with the infection of human HEK293 cell line by the influenza virus and demonstrated, once again, the usefulness of multifrequency scanning permittivity for in‐line monitoring and supervision of cell‐based viral production processes. Published 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013  相似文献   
280.
The aim of this investigation was to evaluate the ability of the indifferent halophyte Sulla carnosa Desf. to desalinize a moderately-salt-affected soil. Seeds were sown on a fertile soil added or not with 1.5 g NaCl. kg?1. Analogous treatments without plantation (control and salinized) were also used. Plant culture was performed under greenhouse conditions in non-perforated pots containing 10 kg soil each and irrigated with non-saline tap water. After 80 days of treatment, shoots were harvested. Soil samples were also collected after division of soil column in each pot into two horizons. Our results showed that salt addition increased electrical conductivity of saturation paste extract (ECe) from 3.3 to 8.4 dS. m?1 and soluble sodium concentration from 0.32 to 1.15 g. kg?1 soil in the upper horizon. In the lower horizon however, Na+ concentration was quasi-constant and then ECe was less increased. Plant culture inversed this pattern of sodium accumulation and salinity. Its productivity and phytodesalination capacity in 80 days were 5.0 t DW. ha?1 and 0.3 t Na+. ha?1 (24% of the added quantity), respectively. Interestingly, sodium dilution within biomass (41.5–45.6 mg. g?1 DW) and the non-altered nutrition make this plant suitable for forage as second use after phytodesalination.  相似文献   
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