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991.
Lee S. Webley Kyall R. Zenger Graham P. Hall Desmond W. Cooper 《European Journal of Wildlife Research》2007,53(1):40-46
European fallow deer are an introduced species classified as partly protected wildlife in Tasmania, Australia. Current management
practices are primarily governed under the Quality Deer Management regime, in which animals are harvested during designated
hunting seasons. Among populations, prominent morphological differences have been reported; however, the genetic relationship
of these populations has until now been poorly understood. Representative animals were sampled from three key areas across
their range and genotyped at ten polymorphic microsatellite loci to investigate genetic diversity, population structure, and
genetic bottlenecks. Allelic richness was low in all three populations and ranged between 2.20 and 2.49 alleles/locus. A genetic
bottleneck was detected in two of the three populations (P < 0.001). Population differentiation was evident between Lake Echo and Benham (q = 0.122; P < 0.001) and Benham and Connorville (q = 0.110; P < 0.001), but not between Lake Echo and Connorville (q = 0.0235), with individuals being identified as belonging to two genetic
clusters. The pattern of population differentiation from the three study populations suggests that deer from the western region
of their range are genetically distinct to those from the eastern region. This correlates with morphological variation within
Tasmanian fallow deer, in which differences between the regions maybe attributable to geographical barriers. 相似文献
992.
Heather E. Johnson Vernon C. Bleich Paul R. Krausman John L. Koprowski 《European Journal of Wildlife Research》2007,53(1):9-15
Although antler size has been identified as a primary determinant of dominance, fighting success, and reproductive success
in male cervids, >80% of the male tule elk (Cervus elaphus nannodes) in the Owens Valley, California, experience antler breakage. To determine the effect of antler breakage on male mating success,
we recorded antler morphology, body size, and mating behavior of male elk throughout the rut. Antler breakage, regardless
of severity, had no effect on male–male assessment, fighting success, or harem-holding status. The factor consistently associated
with our indices of male mating success was not antler size but body size. Although antler size is frequently emphasized as
a key factor in male dominance and social rank, this association may reflect the correlation between antler size and body
size. In the Owens Valley, it appears that male elk are not assessing competitors based on antler morphology but on other
characteristics.
An erratum to this article can be found at 相似文献
993.
The addition of a carbon nutrient feed to a fed-batch cultivation is often not enough to obtain satisfactory growth and/or
production. In some cases, an additional feed with for example supplementary amino acids or complex media is required. This
work presents the development of feeding strategies where more than one feed is required and the knowledge of the growth requirements
is low. Simulations and cultivations with E. coli are shown using the proposed feed controllers which are based on a probing control concept. The strategies work well and
they can be used to shorten the process development phase considerably. 相似文献
994.
Flores A Nisola GM Cho E Gwon EM Kim H Lee C Park S Chung WJ 《Bioprocess and biosystems engineering》2007,30(3):197-205
The performance of enriched sludge augmented with the B21 strain of Alcaligenes defragrans was compared with that of enriched sludge, as well as with pure Alcaligenes defragrans B21, in the context of a sulfur-oxidizing denitrification (SOD) process. In synthetic wastewater treatment containing 100–1,000 mg
NO3−-N/L, the single strain-seeded system exhibited superior performance, featuring higher efficiency and a shorter startup period,
provided nitrate loading rate was less than 0.2 kg NO3−-N/m3 per day. At nitrate loading rate of more than 0.5 kg NO3−-N/m3 per day, the bioaugmented sludge system showed higher resistance to shock loading than two other systems. However, no advantage
of the bioaugmented system over the enriched sludge system without B21 strain was observed in overall efficiency of denitrification.
Both the bioaugmented sludge and enriched sludge systems obtained stable denitrification performance of more than 80% at nitrate
loading rate of up to 2 kg NO3−-N/m3 per day. 相似文献
995.
A bioactive foam reactor (BFR), a novel bioreactor operated using surfactant foams and suspended microorganisms for the treatment
of gaseous toluene, was investigated to characterize its performance with respect to the mass transfer and biodegradation
rates. The BFR system consisted of two reactors in series; a foam column for toluene mass transfer using fine bubbles and
a cell reservoir where suspended microorganisms actively biodegraded toluene. In this study, a series of short-term experiments
demonstrated that the BFR could achieve stable removal performance and a high elimination capacity (EC) for toluene at 100.3 g/m3/h. A numerical model, combining mass balance equations for the mass transfer and subsequent biodegradation, resulted in reasonable
agreement with the experimental findings. At an inlet toluene concentration of 100 ppmv, the toluene concentration in the liquid phase remained extremely low, indicating that the microbial activity was not hindered
in the BFR system. However, the experimental and model prediction results showed that the actual mass of toluene transferred
into the liquid phase was not closely balanced with the amount of toluene biodegraded in the BFR used in this study. Consequently,
methods, such as increasing the effective volume of the foam column or the mass transfer coefficient, need to be implemented
to achieve higher toluene EC and better BFR performance. 相似文献
996.
Fishmeal wastewater, a seafood processing waste, was utilized for production of lactic acid and fungal biomass by Rhizopus oryzae AS 3.254 with the addition of sugars. The 30 g/l exogenous glucose in fishmeal wastewater was superior to starch in view
of productivities of lactic acid and fungal biomass, and COD reduction. Fishmeal wastewater can be a replacement for peptone
which was the most suitable nitrogen source for lactic acid production among the tested organic or inorganic nitrogen sources.
Exogenous NaCl (12 g/l) completely inhibited the production of lactic acid and fungal growth. In the medium of COD 5,000 mg/l
fishmeal wastewater with the addition of 30 g/l glucose, the maximum productivity of lactic acid was 0.723 g/l h corresponding
to productivity of fungal biomass 0.0925 g/l h, COD reduction 84.9% and total nitrogen removal 50.3% at a fermentation time
of 30 h. 相似文献
997.
In these studies, butanol (acetone butanol ethanol or ABE) was produced from wheat straw hydrolysate (WSH) in batch cultures
using Clostridium beijerinckii P260. In control fermentation 48.9 g L−1 glucose (initial sugar 62.0 g L−1) was used to produce 20.1 g L−1 ABE with a productivity and yield of 0.28 g L−1 h−1 and 0.41, respectively. In a similar experiment where WSH (60.2 g L−1 total sugars obtained from hydrolysis of 86 g L−1 wheat straw) was used, the culture produced 25.0 g L−1 ABE with a productivity and yield of 0.60 g L−1 h−1 and 0.42, respectively. These results are superior to the control experiment and productivity was improved by 214%. When
WSH was supplemented with 35 g L−1 glucose, a reactor productivity was improved to 0.63 g L−1 h−1 with a yield of 0.42. In this case, ABE concentration in the broth was 28.2 g L−1. When WSH was supplemented with 60 g L−1 glucose, the resultant medium containing 128.3 g L−1 sugars was successfully fermented (due to product removal) to produce 47.6 g L−1 ABE, and the culture utilized all the sugars (glucose, xylose, arabinose, galactose, and mannose). These results demonstrate
that C. beijerinckii P260 has excellent capacity to convert biomass derived sugars to solvents and can produce over 28 g L−1 (in one case 41.7 g L−1 from glucose) ABE from WSH. Medium containing 250 g L−1 glucose resulted in no growth and no ABE production. Mixtures containing WSH + 140 g L−1 glucose (total sugar approximately 200 g L−1) showed poor growth and poor ABE production.
Mention of trade names or commercial products in this article is solely for the purpose of providing scientific information
and does not imply recommendation or endorsement by the United States Department of Agriculture. 相似文献
998.
999.
Proteins involved in telomere end protection have previously been identified. In Saccharomyces cerevisiae, Cdc13, Yku and telomerase, mainly, prevent telomere uncapping, thus providing telomere stability and avoiding degradation
and death by senescence. Here, we report that in the absence of Mrc1, a component of the replication forks, telomeres of cdc13 or yku70 mutants exhibited increased degradation, while telomerase-negative cells displayed accelerated senescence. Moreover, deletion
of MRC1 increased the single-strandedness of the telomeres in cdc13-1 and yku70Δ mutant strains. An mrc1 deletion strain also exhibited slight but stable telomere shortening compared to a wild-type strain. Loss of Mrc1’s checkpoint
function alone did not provoke synthetic growth defects in combination with the cdc13-1 mutation. Combinations between the cdc13-1 mutation and deletion of either TOF1 or PSY2, coding for proteins physically interacting with Mrc1, also resulted in a synthetic growth defect. Thus, the present data
suggest that non-essential components of the DNA replication machinery, such as Mrc1 and Tof1, may have a role in telomere
stability in addition to their role in fork progression. 相似文献
1000.
Fu BY Xiong JH Zhu LH Zhao XQ Xu HX Gao YM Li YS Xu JL Li ZK 《Molecular genetics and genomics : MGG》2007,278(6):599-609
Drought tolerance (DT) in rice is known to be controlled by many quantitative trait loci (QTLs) and involved differential
expression of large numbers of genes, but linking QTLs with their underlying genes remains the most challenging issue in plant
molecular biology. To shed some light on this issue, differential gene expression in response to PEG simulated drought in
3 unique genetic materials (a lowland rice, IR64 and its derived line, PD86 which has 11 introgressed DT QTLs, and a upland
rice IRAT109) was investigated using a PCR-based subtractive hybridization strategy. More than 300 unique subtracted cDNA
sequences, covering genes of diverse cellular activities and functions, were identified and confirmed by semi-quantitative
and quantitative RT-PCR. Detailed bioinformatics analyses of the data revealed two interesting results. First, the levels
and mechanisms of DT of the three rice lines were associated with the number and types of differentially expressed genes,
suggesting different DT mechanisms in rice are controlled by different sets of genes and different metabolic pathways, and
most differentially expressed genes under drought were able to contribute to DT. Second, there appeared a high correspondence
in genomic location between DT QTLs and clusters of differentially expressed genes in rice, suggesting some DT QTLs may represent
clusters of co-regulated and functionally related genes. Thus, differential gene expression analyses using genetically characterized
materials can provide additional insights into the molecular basis of QTLs and convergent evidence to shortlist the candidate
genes for target QTLs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Bin-Ying Fu and Jian-Hua Xiong are contributed to this work equally. 相似文献