Three artificially selected duck populations (AS), higher lean meat ratios (LTPD), higher fat ratios (FTPD) and higher quality meat (CMD), have been developed in China, providing excellent ...populations for investigation of artificial selection effects. However, the genetic signatures of artificial selection are unclear. In this study, we sequenced the genome sequences of these three artificially selected populations and their ancestral population (mallard, M). We then compared the genome sequences between AS and M and between LTPD and FTPD using integrated strategies such as anchoring scaffolds to pseudo-chromosomes, mutation detection, selective screening, GO analysis, qRT-PCR, and protein multiple sequences alignment to uncover genetic signatures of selection. We anchored duck scaffolds to pseudo-chromosomes and obtained 28 pseudo-chromosomes, accounting for 84% of duck genome in length. Totally 78 and 99 genes were found to be under selection between AS and M and between LTPD and FTPD. Genes under selection between AS and M mainly involved in pigmentation and heart rates, while genes under selection between LTPD and FTPD involved in muscle development and fat deposition. A heart rate regulator (HCN1), the strongest selected gene between AS and M, harbored a GC deletion in AS and displayed higher mRNA expression level in M than in AS. IGF2R, a regulator of skeletal muscle mass, was found to be under selection between FTPD and LTPD. We also found two nonsynonymous substitutions in IGF2R, which might lead to higher IGF2R mRNA expression level in FTPD than LTPD, indicating the two nonsynonymous substitutions might play a key role for the regulation of duck skeletal muscle mass. Taken together, these results of this study provide valuable insight for the genetic basis of duck artificial selection.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To assess the quantification accuracy of pulmonary nodules using virtual monoenergetic images (VMIs) derived from spectral-detector computed tomography (CT) under an ultra-low-dose scan protocol.
A ...chest phantom consisting of 12 pulmonary nodules was scanned using spectral-detector CT at 100 kVp/10 mAs, 100 kVp/20 mAs, 120 kVp/10 mAs, and 120 kVp/30 mAs. Each scanning protocol was repeated three times. Each CT scan was reconstructed utilizing filtered back projection, hybrid iterative reconstruction, iterative model reconstruction (IMR), and VMIs of 40-100 keV. The signal-to-noise ratio and air noise of images, absolute differences, and absolute percentage measurement errors (APEs) of the diameter, density, and volume of the 4 scan protocols and 10 reconstruction images were compared.
With each fixed reconstruction image, the four scanning protocols exhibited no significant differences in APEs for diameter and density (all
> 0.05). Of the 4 scan protocols and 10 reconstruction images, APEs for nodule volume had no significant differences (all
> 0.05). At 100 kVp/10 mAs, APEs for density using IMR were the lowest (APE
: 6.69), but no significant difference was detected between VMIs at 50 keV (APE
: 11.69) and IMR (
= 0.666). In the subgroup analysis, at 100 kVp/10 mAs, there were no significant differences between VMIs at 50 keV and IMR in diameter and density (all
> 0.05). The radiation dose at 100 kVp/10 mAs was reduced by 77.8% compared with that at 120 kVp/30 mAs.
Compared with IMR, reconstruction at 100 kVp/10 mAs and 50 keV provides a more accurate quantification of pulmonary nodules, and the radiation dose is reduced by 77.8% compared with that at 120 kVp/30 mAs, demonstrating great potential for ultra-low-dose spectral-detector CT.
With the rapid development of urban rail transit and underground space development, the occurrence of excavation near existing tunnels is becoming more common. This excavation and unloading will ...inevitably cause soil deformation outside the pit and the tunnel buried therein. This paper presents an investigation into the entire excavation process and the deformation effects on the adjacent subway structure under complex construction environments, including soft soil foundations and adjacent subway intersections, based on measured data of pit construction. The horizontal and vertical displacements of deep soils in two pits were analyzed along with safety management measures to determine the horizontal displacement curve pattern and the lateral displacement development distribution law of deep soils. The analysis of subway deformation data shows that after excavation, the subway tunnel undergoes “lateral expansion” and “vertical compression” type deformation, accompanied by “in-pit” horizontal displacement and “settlement” vertical displacement. Furthermore, a correlation analysis reveals a clear linear relationship between pit deformation and subway structure deformation, which can be used as a prediction method for adjacent structure deformation. Finally, a comparative analysis of existing relevant influence zone models and tunnel deformation prediction formulas is carried out based on the monitoring. The results of this study have significant guiding implications for the excavation construction of soft soil foundations in the vicinity of subway crossings.
Bone marrow stromal cells (MSCs) were used as cell therapy for various diseases in recent years. Some reports showed that transplanted MSCs promote functional recovery in animal models of brain ...trauma. But other studies indicate that tissue replacement by this method may not be the main source of therapeutic benefit. Neurotrophic factors such as brain-derived neurotrophic factor (BDNF) therapeutic potential may contribute to the recovery of function after trauma. Our previous study showed that BDNF–MSCs could promote the survival of neurons in neuronal injured models in vitro. The present study was undertaken to explore the therapeutic effects of MSCs transfected with BDNF in vivo. After intraventricular injection of MSCs–BDNF, BDNF levels were increased significantly in cerebrospinal fluid by ELISA. Further studies showed that treatment of traumatic brain injury with MSCs–BDNF could attenuate neuronal injury as measurement of biological behavior assessment. These studies demonstrate that by increasing the brain concentration of BDNF, intraventricularly transplanted MSCs–BDNF might play an important role in the treatment of traumatic brain injury and might be an optional therapeutic strategy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Studying how to use the coupling characteristics of net aberration fields induced by different perturbation parameters to realize the wave aberration compensation correction of perturbed telescopes ...is of great significance for the development of active optics. Based on nodal aberration theory, this paper studies the wave aberration compensation correction method of an unobscured off-axis three-mirror telescope. Specifically, first of all, it theoretically analyzes the coupling effects and compensation relationships of net aberration fields induced by different perturbation parameters of the telescope. Furthermore, it establishes wave aberration correction models with the secondary mirror as the compensator and the third mirror as the compensator for the telescope, respectively. In the end, it verifies the two compensation correction models by simulations. The results show that the tolerance of the secondary mirror compensation correction mode (SMCM) to the perturbation parameter threshold is significantly better than that of the third mirror compensation correction model (TMCM). When the introduced perturbation parameter threshold is small, the correction accuracy of the two models for the wave aberrations is equivalent, and both reach the order of 10−3λ (RMS, λ = 632.8 nm). When the perturbation parameter threshold is increased, the correction accuracy of SMCM can still be maintained at the order of 10−3λ but the correction accuracy of TMCM would decrease by an order of magnitude.
Due to the variety of devices and operating scenarios in an integrated energy system (IES), the optimal dispatch of an IES is usually complicated. An optimal dispatch method for an IES is proposed by ...defining the scheduling value for each device which can be different under various scenarios. First, thinking over the private and public attributes of each operating equipment, the evaluation system is established with the actual scenarios of economic, environmental and energy-savings being considered. Secondly, the economic, environmental and energy-saving benefits of each operating equipment are quantified by Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS). Therefore, the scheduling value of the device is comprehensively assessed according to the specific scenario. Finally, decomposing the output of the device into direct available energy and indirect available energy, an optimal model is built with the maximum general production benefits as the objective, and is solved by MATLAB and CPLEX. The simulation results show that the evaluation system can reflect multiple values of devices. The proposed model can unify the modeling of optimal dispatch for different scenarios in the IES and can improve dispatch efficiency, while ensuring the accuracy of the results with high computation efficiency.
In view of the world-wide problem of energy sustainability and greenhouse gas production (carbon dioxide), it is timely to review the issues involved in generating heat and power from all fuels and ...especially new (to the UK) solid fuels, including high moisture fuels such as wood, SRF, oil shale, tar sands and brown coal, which will become major international fuels as oil and gas become depleted. The combustion properties of some of these materials are significantly different from traditional coal, oil and gas fuels, however the technology proposed herein is also applicable to these conventional fuels.
This paper presents some innovative combustion system options and the associated technical factors that must be considered for their implementation. For clarity of understanding, the novel concepts will be largely presented in terms of a currently developing solid fuel market; biomass wood chips.
One of the most important characteristics of many solid fuels to be used in the future (including oil shale and brown coal) is their high moisture content of up to 60%. This could be removed by utilising low grade waste heat that is widely available in industry to dry the fuel and thus reduce transport costs. Burning such dried wood for power generation also increases the energy available from combustion and thus acts as a thermal transformer by upgrading the low grade heat to heat available at combustion temperatures.
The alternative approach presented here is to recover the latent heat by condensing the extrinsic moisture and the water formed during combustion. For atmospheric combustion, the temperature of the condensed combustion products is below the dew point at about 55–65 °C and is only suitable for recovery in an efficient district heating system. However, in order to generate power from the latent heat, the condensation temperature must be increased to the level where the heat can be used in the thermodynamic power cycle. This can be achieved by increasing the combustion pressure to above 80 bar, resulting in the recovered latent heat being available at more than 200 °C. It can then be used to increase the cycle efficiency by about 15% by pre-heating the boiler water and/or combustion air etc. A further advantage is that the high pressure of the combustion gases also reduces the superheater tube stress since it can balance the steam pressure.
The key advantage of this high pressure flue gas is that it is above the pressure at which carbon dioxide ‘condenses’ to a liquid or supercritical gas at atmospheric temperature. Thus when used with oxy-fuel combustion, the carbon dioxide flue gas from which the moisture has been condensed can be cooled to atmospheric temperature and the supercritical CO2 can be fed directly into the pipes leading to the sequestration site. An important consideration of these strategies is to ensure that non-condensable gases in the exhaust, including oxygen and nitrogen, do not adversely affect the ‘condensation’ processes.
When oxy-fuel combustion is used, the flame temperature must be moderated by a cool diluent. Recycled carbon dioxide is often proposed for this duty. However, since the latent heat is recovered, the moisture or even additional water can fulfil this role. This latter option may be advantageous since it is more efficient to pump wood chip fuel in water into the high pressure zone rather than feed solid wood particles. Surplus water can be simply drained and the wet wood chips are a good fuel when the latent heat of the moisture in the fuel gases is recovered into the power cycle.
Bearing in mind that it is much more efficient to pump a liquid to high pressure than to compress the same material as a gas, indicates that cryogenic oxygen is a suitable material to use for an efficient power station that generates energy from biomass (or other fuels such as coal etc).
Finally, combustion of the hydrogen from the water–gas reaction with oxygen allows the steam temperature in the turbine to be increased to the “gas-turbine engine” range of 1000–1400 °C and hence the biomass and/or fossil fuel cycle efficiency can be well over 60%!
► Innovative combustion system options and technical implementation for high moisture fuels. ► High pressure oxy-fuel combustion system increases the cycle efficiency by 15%. ► Liquid CO2 can be formed at ambient temperature and fed directly into pipes for sequestration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background
Traditional crop breeding has made significant achievement meet food needs worldwide. However, the way has some inevitable problems including time-consuming, laborious, low predictability ...and reproducibility. In this study, we updated the
GRAIN SIZE 3 (GS3)
locus to improve the grain length of a major cultivate variety of Kongyu 131 at Heilongjiang Province, the northernmost region of China. High-resolution melting (HRM) analysis is used for single nucleotide polymorphism (SNP) genotyping.
Results
The improved line introgressed about 117 kb segment including
gs3
allele from donor GKBR by using five SNP markers designed within and without
GS3
locus, and the background recovery ratio of the recurrent parent genome is about 99.55% that are detected by 219 SNP markers evenly distributed on the 12 chromosomes. The field trial indicates that grain length, 100-grain weight and total grain weight per plant of the improved line raised by 12.05%, 16.30% and 4.47%, respectively, compared with Kongyu 131.
Conclusions
This result demonstrates that update the
GS3
locus is a feasible and efficient and accurate way can be applied to improve grain size of rice.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background
Kongyu 131 is an elite
japonica
rice variety of Heilongjiang Province, China. It has the characteristics of early maturity, superior quality, high yield, cold tolerance and wide ...adaptability. However, there is potential to improve the yield of Kongyu 131 because of the relatively few grains per panicle compared with other varieties. Hence, we rebuilt the genome of Kongyu 131 by replacing the
GRAIN NUMBER1a
(
Gn1a
) locus with a high-yielding allele from a big panicle
indica
rice variety, GKBR. High-resolution melting (HRM) analysis was used for single nucleotide polymorphism (SNP) genotyping.
Results
Quantitative trait locus (QTL) analysis of the BC
3
F
2
population showed that the introgressed segment carrying the
Gn1a
allele of GKBR significantly increased the branch number and grain number per panicle. Using 5 SNP markers designed against the sequence within and around
Gn1a
, the introgressed chromosome segment was shortened to approximately 430 Kb to minimize the linkage drag by screening recombinants in the target region. Genomic components of the new Kongyu 131 were detected using 220 SNP markers evenly distributed across 12 chromosomes, suggesting that the recovery ratio of the recurrent parent genome (RRPG) was 99.89%. Compared with Kongyu 131, the yield per plant of the new Kongyu 131 increased by 8.3% and 11.9% at Changchun and Jiamusi, respectively.
Conclusions
To achieve the high yield potential of Kongyu 131, a minute chromosome fragment carrying the favorable
Gn1a
allele from the donor parent was introgressed into the genome of Kongyu 131, which resulted in a larger panicle and subsequent yield increase in the new Kongyu 131. These results indicate the feasibility of improving an undesirable trait of an elite variety by replacing only a small chromosome segment carrying a favorable allele.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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