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Airborne pollen and spore levels were monitored at seven sites in New Zealand using the Intermittent Cycling Rotorod sampler
during the summer of 1988/1989. Grasses formed the major component of atmospheric pollen levels during spring and summer at
every locality. Peak levels of grass and total pollen occurred during December or late November, with a slight latitudinal
lag apparent at the more southern sites. Highest levels were recorded at the smaller rural centres of Gore and Kaikohe and
the lowest at the larger urban centres of Auckland, Christchurch and Wellington. We make a first approximation of the likely
risk to hayfever and allergic asthma patients at each of the seven centres. For example, significantly higher grass pollen
levels were experienced at Kaikohe on 44% and 65% of days during November and December, compared with just 15% and 8% at Auckland.
By recording the flowering seasons of the principal allergenic grass species at each locality, we determined the potentially
allergenic grasses contributing to peak pollen levels, the most ubiquitous being tall fescue (Festuca arundinacea Schreb.), ryegrass (Lolium perenne L.,L. multiflorum Lam.), cocksfoot (Dactylis glomerata L.), Yorkshire fog (Holcus lanatus L.) and sweet vernal (Anthoxanthum odoratum L.).
Corresponding author. Deceased. 相似文献
25.
Genomics meets applied ecology: Characterizing habitat quality for sloths in a tropical agroecosystem
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Emily D. Fountain Jung koo Kang Douglas J. Tempel M. Zachariah Peery 《Molecular ecology》2018,27(1):41-53
Understanding how habitat quality in heterogeneous landscapes governs the distribution and fitness of individuals is a fundamental aspect of ecology. While mean individual fitness is generally considered a key to assessing habitat quality, a comprehensive understanding of habitat quality in heterogeneous landscapes requires estimates of dispersal rates among habitat types. The increasing accessibility of genomic approaches, combined with field‐based demographic methods, provides novel opportunities for incorporating dispersal estimation into assessments of habitat quality. In this study, we integrated genomic kinship approaches with field‐based estimates of fitness components and approximate Bayesian computation (ABC) procedures to estimate habitat‐specific dispersal rates and characterize habitat quality in two‐toed sloths (Choloepus hoffmanni) occurring in a Costa Rican agricultural ecosystem. Field‐based observations indicated that birth and survival rates were similar in a sparsely shaded cacao farm and adjacent cattle pasture–forest mosaic. Sloth density was threefold higher in pasture compared with cacao, whereas home range size and overlap were greater in cacao compared with pasture. Dispersal rates were similar between the two habitats, as estimated using ABC procedures applied to the spatial distribution of pairs of related individuals identified using 3,431 single nucleotide polymorphism and 11 microsatellite locus genotypes. Our results indicate that crops produced under a sparse overstorey can, in some cases, constitute lower‐quality habitat than pasture–forest mosaics for sloths, perhaps because of differences in food resources or predator communities. Finally, our study demonstrates that integrating field‐based demographic approaches with genomic methods can provide a powerful means for characterizing habitat quality for animal populations occurring in heterogeneous landscapes. 相似文献
26.
Evolution and characterisation of the AhRAF4 NB‐ARC gene family induced by Aspergillus flavus inoculation and abiotic stresses in peanut
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![点击此处可从《Plant biology (Stuttgart, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Y. Deng H. Chen C. Zhang T. Cai B. Zhang S. Zhou J. C. Fountain R.‐L. Pan B. Guo W.‐J. Zhuang 《Plant biology (Stuttgart, Germany)》2018,20(4):737-750
- Aflatoxin contamination in peanut is a serious food safety issue to human health around the world. Finding disease resistance genes is a key strategy for genetic improvement in breeding to deal with this issue.
- We identified an Aspergillus flavus‐induced NBS‐LRR gene, AhRAF4, using a microarray‐based approach. By comparison of 23 sequences from three species using phytogenetics, protein secondary structure and three‐dimensional structural analyses, AhRAF4 was revealed to be derived from Arachis duranensis by recombination, and has newly evolved into a family of several members, characterised by duplications and point mutations. However, the members of the family descended from A. ipaensis were lost following tetraploidisation.
- AhRAF4 was slightly up‐regulated by low temperature, drought, salicylic acid and ethylene, but down‐regulated by methyl jasmonate. The distinct responses upon As. flavus inoculation and the differential reactions between resistant and susceptible varieties indicate that AhRAF4 might play a role in defence responses. Temporal and spatial expression and the phenotype of transformed protoplasts suggest that AhRAF4 may also be associated with pericarp development.
- Because tetraploid cultivated peanuts are vulnerable to many pathogens, an exploration of R‐genes may provide an effective method for genetic improvement of peanut cultivars.
27.
L-Lactate dehydrogenase (L-LDH, E.C. 1.1.1.27) is encoded by two or three
loci in all vertebrates examined, with the exception of lampreys, which
have a single LDH locus. Biochemical characterizations of LDH proteins have
suggested that a gene duplication early in vertebrate evolution gave rise
to Ldh-A and Ldh-B and that an additional locus, Ldh-C arose in a number of
lineages more recently. Although some phylogenetic studies of LDH protein
sequences have supported this pattern of gene duplication, others have
contradicted it. In particular, a number of studies have suggested that
Ldh-C represents the earliest divergence among vertebrate LDHs and that it
may have diverged from the other loci well before the origin of
vertebrates. Such hypotheses make explicit statements about the
relationship of vertebrate and invertebrate LDHs, but to date, no closely
related invertebrate LDH sequences have been available for comparison. We
have attempted to provide further data on the timing of gene duplications
leading to multiple vertebrate LDHs by determining the cDNA sequence of the
LDH of the tunicate Styela plicata. Phylogenetic analyses of this and other
LDH sequences provide strong support for the duplications giving rise to
multiple vertebrate LDHs having occurred after vertebrates diverged from
tunicates. The timing of these LDH duplications is consistent with data
from a number of other gene families suggesting widespread gene duplication
near the origin of vertebrates. With respect to the relationships among
vertebrate LDHs, our data are not consistent with previous claims that
Ldh-C represented the earliest divergence. However, the precise
relationships among some of the main lineages of vertebrate LDHs were not
resolved in our analyses.
相似文献
28.
Christopher J Lelliott Gema Medina-Gomez Natasa Petrovic Adrienn Kis Helena M Feldmann Mikael Bjursell Nadeene Parker Keira Curtis Mark Campbell Ping Hu Dongfang Zhang Sheldon E Litwin Vlad G Zaha Kimberly T Fountain Sihem Boudina Mercedes Jimenez-Linan Margaret Blount Miguel Lopez Aline Meirhaeghe Mohammad Bohlooly-Y Leonard Storlien Maria Strmstedt Michael Snaith Matej Orei
E. Dale Abel Barbara Cannon Antonio Vidal-Puig 《PLoS biology》2006,4(11)
29.
Cephaloridine and cephalexin had no effect on ribonucleic acid (RNA), deoxyribonucleic acid (DNA), or protein synthesis in Escherichia coli. However, cephalosporin 7/30 [7-(S-benzylthioacetamido)-cephem-3-ylmethyl-N -dimethyldithiocarbamate-4-carboxylic acid] and dimethyldithiocarbamate (DMDT), which occupies the side chain at position 3 in the 7/30 molecule, inhibited protein synthesis (and, to a lesser extent, RNA and DNA syntheses) in E. coli and had an inhibitory effect on the growth of Saccharomyces carlsbergensis. A bioautograph technique showed that two inhibitory spots were obtained with 7/30 but only one such spot with cephaloridine. Release of DMDT onto or in the bacterial cell may be responsible for "unusual" mode of action of cephalosporin 7/30. 相似文献
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