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31.
L. K. Ignatova N. S. Novichkova V. A. Mudrik V. Yu. Lyubimov B. N. Ivanov A. K. Romanova 《Russian Journal of Plant Physiology》2005,52(2):158-164
The effects of CO2 concentration (C
a) on growth, photosynthesis, and the activity of enzymes associated with the translocation and assimilation of CO2 were studied in sugar beet (Beta vulgaris L. subsp. saccharifera, cv. Ramonskaya) plants. The plants were grown in controlled-climate chamber to the stage of 3–4 leaves and then used in experiments. Experimental plants were exposed in boxes to doubled C
a (700 µl/l, 2C plants), whereas control plants were kept in a chamber with ambient atmosphere (350 µl/l, 1C plants). As compared with 1C plants, in 3 and 8 days, the leaf area of 2C plants increased by 14 and 26%, respectively. The rate of their photosynthesis (P
n) measured in 3, 6, and 8 days increased by 85, 47, and 52%, respectively, whereas in normal air, the values of P
n in 2C plants were by 12, 19, and 15% lower than in 1C plants. After 8-day growth, the content of soluble carbohydrates in the leaves of 2C plants attained 7.2%, being by 80% greater than in 1C plants; the content of starch did not exceed 3%. The total content of chlorophylls a and b in the leaves of 2C plants was by 14% greater than in 1C plants, but their ratio was essentially the same. The level of protein in 2C plants was by 13.4% lower than in 1C plants. The activity and content of Rubisco in 1C and 2C plants were similar. As compared with 1C plants, in 2C plants the activity of soluble carbonic anhydrase (sCA) was lower by 34% in 3 days and by 18% in 8 days; the activity of carbonic anhydrase of membrane preparations (mCA), was lower by 24 and 77%, respectively. Catalase activity in 2C plants became by 8% lower than in 1C plants only after 8 days. A reduction in the photosynthetic ability of 2C plants in ambient atmosphere, a decrease in activity of sCA and, especially, of mCA observed together with invariable activity and content of Rubisco in the leaf extracts are interpreted as early symptoms of acclimation of young plants of sugar beet to elevated CO2.Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 184–190.Original Russian Text Copyright © 2005 by Ignatova, Novichkova, Mudrik, Lyubimov, Ivanov, Romanova.This revised version was published online in April 2005 with a corrected cover date. 相似文献
32.
The kinetic curves of dark reduction of P700+ (oxidized primary donor of PSI) after far-red light irradiation were studied on broad bean (Vicia faba L.) leaves treated with antimycin A, methyl viologen, or diuron. Four components of P700+ reduction were found in untreated leaves, namely, an ultrafast component with a half-time of 25 ms, and fast (210 ms), middle (790 ms), and slow (6100 ms) components. The fast component disappeared in leaves treated with antimycin A or methyl viologen. At the same time, these substances did not affect other components of P700+ reduction. Treatment of leaves with diuron abolished both the ultrafast and fast components of P700+ reduction. As the length of far-red light exposure was increased, a lag phase appeared in the development of middle component in leaves treated with diuron, antimycin A, or methyl viologen. In thus treated leaves, an exponential pattern of the middle component was displayed with a certain delay after darkening. A conclusion was drawn that the minor ultrafast component of P700+ dark reduction in broad bean leaves was caused by electron donation to PSI from PSII, whereas the fast component of this process was determined by the operation of ferredoxin-dependent electron transport around PSI. The middle and slow components were supposed to be related to electron input to PSI from reductants localized in the chloroplast stroma.From Fiziologiya Rastenii, Vol. 52, No. 4, 2005, pp. 492–498.Original English Text Copyright © 2005 by Egorova, Nikolaeva, Bukhov.The article was translated by the authors. 相似文献
33.
Piero Genovesi 《Biological invasions》2005,7(1):127-133
Eradication of alien species is a key conservation tool to mitigate the impacts caused by biologic invasions. The aim of the
present paper is to review the eradications successfully completed in Europe and to discuss the main limits to a wider application
of this management option in the region. On the basis of the available literature – including conference proceedings, national
reports to the Bern Convention, etc. – a total of 37 eradication programmes have been recorded. Thirty-three eradications
were carried out on islands and four on the mainland. The rat (Rattus spp.) has been the most common target (n = 25, 67%), followed by the rabbit (n = 4). In many cases, these eradications determined a significant recovery of native biodiversity. Differently to other regions
of the world, no eradications of alien invertebrates and marine organisms have been recorded; regarding invasive alien plants,
it appears that only some very localized removals have been completed so far in Europe. The limited number of eradications
carried out in Europe so far is probably due to the limited awareness of the public and the decision makers, the inadequacy
of the legal framework, and the scarcity of resources. Synthetic guidelines for improving the ability of European states to
respond to aliens incursions are presented.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
34.
Dorothy Guzowski Alamelu Chandrasekaran Craig Gawel Jacqueline Palma Jonathan Koenig Xue Ping Wang Michael Dosik Mark Kaplan Charles C Chu Sangeeta Chavan Richard Furie Emilia Albesiano Nicholas Chiorazzi Leslie Goodwin 《Journal of biomolecular techniques》2005,16(2):154-166
Interleukin-10 (IL10), an anti-inflammatory cytokine, has been implicated in a variety of immune- and inflammatory-related diseases. We investigated the following SNPs: -1082, -819, -592 in the promoter region of IL10 in a normal (control) population and selected diseases: breast cancer (BrCa), systemic lupus erythematosus (SLE), and B-cell chronic lymphocytic leukemia (B-CLL) by denaturing high-performance liquid chromatography (DHPLC) and found distinct genotype and haplotype patterns. DHPLC was performed using the Transgenomic WAVE instrument, a mutational discovery tool that allows for high throughout analysis of SNPs. The principle of DHPLC is based on separation of homo- and heteroduplex formation of individual polymerase chain reaction products at specific melting temperatures and set gradients. The melting temperature selected for each SNP was based on size and sequence of the polymerase chain reaction product (for -1082, 57 degrees C; for -819, 58 degrees C; and for -592, 59.2 degrees C). Before fragment mutational analysis, all samples were denatured at 95 degrees C and slowly reannealed to allow for reassociation of different strands. Heteroduplex samples were easily distinguished from homoduplex samples. In order to identify wild type from homozygous mutant, two homoduplex polymerase chain reaction samples had to be mixed together, denatured at 95 degrees C and reannealed. The homozygous mutant, when combined with wild type, displayed a double peak on chromatogram. Once distinct chromatograms were established for each of the SNPs and the nucleotide changes confirmed by sequencing, genotype and haplotype frequencies were tabulated for the groups studied. 相似文献
35.
36.
W. Brodacz 《Mycotoxin Research》2005,21(1):11-14
Gas chromatography combines high resolution with good sensitivity (ECD) for the simultaneous analysis of trichothecenes. With
the aid of computer-supported GC simulation based on thermodynamic retention indices, optimized GC methods for 4 different
phase polarities have been developed. The verification with polar and unpolar columns in 2 GCs under optimized separation
conditions provides highly reliable results.
Presented at the 26th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004 相似文献
37.
Phylogenetic relationships in the subgenus Mus (genus Mus, family Muridae, subfamily Murinae): examining gene trees and species trees 总被引:1,自引:0,他引:1
PRISCILLA K. TUCKER SARA A. SANDSTEDT BARBARA L. LUNDRIGAN 《Biological journal of the Linnean Society. Linnean Society of London》2005,84(3):653-662
Over eight kilobases (kb) of sequence from eight genes including two mitochondrial loci, Cyt b and 12S, and six nuclear loci, B2m , Zp3 , Tcp1, Sry, Smcx and Smcy , were used to investigate phylogenetic relationships among 11 taxa representing eight species within the rodent genus Mus . Particular attention was given to discerning relationships among species within the subgenus Mus including members of a Palearctic clade ( M. musculus , M. spicilegus , M. macedonicus and M. spretus ) and members of an Asian clade ( M. caroli , M. cookii and M. cervicolor ), as previous studies using different datasets have produced different topologies for taxa within these two groups. While parsimony analyses of the combined eight-gene dataset yielded a single, fully resolved tree, support values were lower for nodes resolving relationships within the Palearctic and Asian clades than they were elsewhere in the tree. In addition, a maximum likelihood analysis of the same eight-gene dataset yielded different topologies for both the Palearctic and the Asian clades. Both observations are indicative of clade instability. The nature of this instability was explored through a comparison with our previous study in which we included the two mitochondrial loci and only four of the six nuclear genes, and through an analysis of partitioned data, specifically mitochondrial vs. nuclear genes. This study underscores the importance of considering among-site rate variation in phylogeny reconstruction. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 653–662. 相似文献
38.
Hans Frauenfelder 《Journal of biological physics》2005,31(3-4):413-416
Proteins are not isolated homogeneous systems. Each protein can exist in a very large number of conformations (conformational
substates) that are characterized by an energy landscape. The main conformational motions, similar to the α and β fluctuations
in glasses, are linked to fluctuations in the bulk solvent and the hydration shell. 相似文献
39.
Emulsion stabilizing properties of various chitosans in the presence of whey protein isolate 总被引:1,自引:0,他引:1
The emulsion stabilizing potential of chitosans (CN) with various molecular weights and degrees of deacetylation (CNI=1494 kDa, 78.1%DD; CNHI=694 kDa, 78.5%DD; CNHI2=319 kDa, 78.5%DD; CNHK=749 kDa, 67.7%DD) was compared in the presence of whey protein isolate. Phase separation evolutions revealed minimal stabilizing concentrations against syneresis from 0.1 to 0.125% in most CN preparations, except CNHI2 where it was higher (0.225%). Those stabilizing concentrations are the result of interfacial coadsorption saturation of CN with proteins, favouring interfacial electrostatic and steric stabilizing mechanisms. The emulsion characteristics (droplet size, limiting low-shear viscosity, and surface net charge), mostly distinctive at 0.1%CN, revealed the following order of stabilizing potentials: CNI≈CNHI>CNHK>CNHI2, which is in agreement with respective phase separation evolutions. The lower stabilizing potential of CNHI2 is explained by lower interfacial coadsorption efficiency with protein. In spite of a higher interfacial load of CNHK vs. CNI and CNHI, its lower stabilizing potential is essentially explained by a lower surface net charge. 相似文献
40.
Reclaiming Applied Anthropology: Its Past, Present, and Future 总被引:1,自引:0,他引:1
Growing concerns about anthropology's impact in both academia and the broader social arena have led to calls for more "public" and more relevant anthropology. In this article, we expand on these exhortations, by calling for systematic joining of critical social theory with application and pragmatic engagement with contemporary problems. We argue for the repositioning of applied anthropology as a vital component of the broader discipline and suggest that it should serve as a framework for constructing a more engaged anthropology. In revisiting disciplinary history and critiques of applied anthropology, we demonstrate the central role that application has played throughout anthropology's evolution, address common misconceptions that serve as barriers to disciplinary integration, examine the role of advocacy in relation to greater engagement as well as the relationship of theory to practice, and conclude with an assessment of the diverse work that is subsumed under the inclusive rubric of "anthropology in use." 相似文献