274 research outputs found
Identification of genes differentially expressed in Jining Grey and Liaoning Cashmere goats ovaries
To search for genes controlling high prolificacy of Chinese indigenous goats, differential display reverse transcription-polymerase chain reaction (DDRT-PCR) was used to screen differentially expressed cDNA bands in the sexually matured ovaries of 3-year-old prolific Jining Grey goats and monotocous Liaoning Cashmere goats with 24 combinations of three anchored primers and eight arbitrary primers. 22 expressed sequence tags (ESTs) were proved to be the positive bands by Northern hybridization. They comprised 10 known ESTs and 12 ESTs without homologous sequences in the GenBank. These results indicate that several genes such as GATA-4, metallothionein-like protein, CAT genes and unknown ESTs (CV983340 and CV983341) were expressed only in Jining Grey goats.Keywords: Differential display reverse transcription-polymerase chain reaction, goat, ovary, prolificacyAfrican Journal of Biotechnology Vol. 12(27), pp. 4408-441
Pacific warm pool excitation, earth rotation and El Niño southern oscillations
2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Spatio-Temporal Characteristics of Global Warming in the Tibetan Plateau during the Last 50 Years Based on a Generalised Temperature Zone - Elevation Model
Temperature is one of the primary factors influencing the climate and ecosystem, and examining its change and fluctuation could elucidate the formation of novel climate patterns and trends. In this study, we constructed a generalised temperature zone elevation model (GTEM) to assess the trends of climate change and temporal-spatial differences in the Tibetan Plateau (TP) using the annual and monthly mean temperatures from 1961-2010 at 144 meteorological stations in and near the TP. The results showed the following: (1) The TP has undergone robust warming over the study period, and the warming rate was 0.318°C/decade. The warming has accelerated during recent decades, especially in the last 20 years, and the warming has been most significant in the winter months, followed by the spring, autumn and summer seasons. (2) Spatially, the zones that became significantly smaller were the temperature zones of -6°C and -4°C, and these have decreased 499.44 and 454.26 thousand sq km from 1961 to 2010 at average rates of 25.1% and 11.7%, respectively, over every 5-year interval. These quickly shrinking zones were located in the northwestern and central TP. (3) The elevation dependency of climate warming existed in the TP during 1961-2010, but this tendency has gradually been weakening due to more rapid warming at lower elevations than in the middle and upper elevations of the TP during 1991-2010. The higher regions and some low altitude valleys of the TP were the most significantly warming regions under the same categorizing criteria. Experimental evidence shows that the GTEM is an effective method to analyse climate changes in high altitude mountainous regions
Experimental review of oxygen content at mixing layer in cone calorimeter
This work aims to elucidate whether the hypothesis of zero oxygen at the mixture layer when flame takes place is assumable for every kind of material. For that purpose, we investigated the oxygen concentration there by cone calorimeter tests. A modified holder was developed in order to collect oxygen in this mixture layer. In addition, thermogravimetric tests were carried out so as to relate the possible effects of the presence of oxygen in the atmosphere where the pyrolysis process takes place, since the cone calorimeter does not allow to control the oxygen level of the atmosphere during the experiment. The reaction rates and per cent of residue in the cone calorimetric tests were measured and compared with the results from thermogravimetric tests. Six products were analysed which can be classified in three main groups: lignocellulosic, thermoplastic polymers and thermoset polymers. Cone calorimetric results showed that for some of the materials analysed (PET, Nylon and PUR foam) the oxygen level at mixture layer decreased until values close to zero. The comparison of reaction rates between cone calorimetric and thermogravimetric tests revealed the char layer created in cone calorimetric tests over the exposed face for brushed fir, Nylon and PET established an important heat barrier that modifies the thermal behaviour of these materials.Authors would like to thank to the Spanish Ministry of Economy and Competitiveness for the PYRODESIGN Project grant, Ref.: BIA2012-37890, financed jointly by FEDER funds
The Impact of Imputation on Meta-Analysis of Genome-Wide Association Studies
Genotype imputation is often used in the meta-analysis of genome-wide association studies (GWAS), for combining data from different studies and/or genotyping platforms, in order to improve the ability for detecting disease variants with small to moderate effects. However, how genotype imputation affects the performance of the meta-analysis of GWAS is largely unknown. In this study, we investigated the effects of genotype imputation on the performance of meta-analysis through simulations based on empirical data from the Framingham Heart Study. We found that when fix-effects models were used, considerable between-study heterogeneity was detected when causal variants were typed in only some but not all individual studies, resulting in up to âŒ25% reduction of detection power. For certain situations, the power of the meta-analysis can be even less than that of individual studies. Additional analyses showed that the detection power was slightly improved when between-study heterogeneity was partially controlled through the random-effects model, relative to that of the fixed-effects model. Our study may aid in the planning, data analysis, and interpretation of GWAS meta-analysis results when genotype imputation is necessary
Bovine GDF10 gene polymorphism analysis and its association with body measurement traits in Chinese indigenous cattle
The objective of this research was to detect bovine GDF10 gene polymorphism and analyze its association with body measurement traits (BMT) of animals sampled from 6 different Chinese indigenous cattle populations. The populations included Xuelong (Xl), Luxi (Lx), Qinchuan (Qc), Jiaxian red (Jx), Xianang (Xn) and Nanyang (Ny). Blood samples were taken from a total of 417 female animals stratified into age categories of 12â36Â months. Polymerase chain reactionâsingle strand conformation polymorphism (PCRâSSCP) was employed to find out GDF10 single polymorphism nucleotide (SNPs) and explore their possible association with BMT. Sequence analysis of GDF10 gene revealed 3 SNPs in total: 1 in exon1 (G142A) and 2 in exon3 (A11471G, and T12495C). G142A and T12495C SNPs are both synonymous mutation. They showed 2 genotypes namely respectively (GG, GA) and (PP and PB). A11471G SNP is a missense mutation leading to the change of Alanine to Threonine amino acid. It showed three genotypes namely AA, BB and AB. Analysis of association of polymorphism with body measurement traits at the three locus showed that there were significant effects on BMT in Qc, Jx and Ny cattle population. These results suggest that the GDF10 gene might have potential effects on body measurement traits in the above mentioned cattle populations and could be used for marker-assisted selection
Mitochondrial haplogroup B increases the risk for hearing loss among the Eastern Asian pedigrees carrying 12S rRNA 1555A>G mutation
Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay
The decay channel
is studied using a sample of events collected
by the BESIII experiment at BEPCII. A strong enhancement at threshold is
observed in the invariant mass spectrum. The enhancement can be fit
with an -wave Breit-Wigner resonance function with a resulting peak mass of
and a
narrow width that is at the 90% confidence level.
These results are consistent with published BESII results. These mass and width
values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics
Front-like entire solutions for monostable reaction-diffusion systems
This paper is concerned with front-like entire solutions for monostable
reactiondiffusion systems with cooperative and non-cooperative nonlinearities.
In the cooperative case, the existence and asymptotic behavior of spatially
independent solutions (SIS) are first proved. Combining a SIS and traveling
fronts with different wave speeds and directions, the existence and various
qualitative properties of entire solutions are then established using
comparison principle. In the non-cooperative case, we introduce two auxiliary
cooperative systems and establish some comparison arguments for the three
systems. The existence of entire solutions is then proved via the traveling
fronts and SIS of the auxiliary systems. Our results are applied to some
biological and epidemiological models. To the best of our knowledge, it is the
first work to study the entire solutions of non-cooperative reaction-diffusion
systems
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