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Abstract Background Genome-wide association studies (GWAS) are an effective way to explore genotype–phenotype associations in humans, animals, and plants. Various GWAS methods have been developed based on different genetic or statistical assumptions. However, no single method is optimal for all traits and, for many traits, the putative single nucleotide polymorphisms (SNPs) that are detected by the different methods do not entirely overlap due to the diversity of the genetic architecture of complex traits. Therefore, multi-tool-based GWAS strategies that combine different methods have been increasingly employed. To take this one step further, we propose an ensemble-like GWAS strategy (E-GWAS) that statistically integrates GWAS results from different single GWAS methods. Results E-GWAS was compared with various single GWAS methods using simulated phenotype traits with different genetic architectures. E-GWAS performed stably across traits with different genetic architectures and effectively controlled the number of false positive genetic variants detected without decreasing the number of true positive variants. In addition, its performance could be further improved by using a bin-merged strategy and the addition of more distinct single GWAS methods. Our results show that the numbers of true and false positive SNPs detected by the E-GWAS strategy slightly increased and decreased, respectively, with increasing bin size and when the number and the diversity of individual GWAS methods that were integrated in E-GWAS increased, the latter being more effective than the bin-merged strategy. The E-GWAS strategy was also applied to a real dataset to study backfat thickness in a pig population, and 10 candidate genes related to this trait and expressed in adipose-associated tissues were identified. Conclusions Using both simulated and real datasets, we show that E-GWAS is a reliable and robust strategy that effectively integrates the GWAS results of different methods and reduces the number of false positive SNPs without decreasing that of true positive SNPs.

The potential for secondary-combustion with low-temperature solid propellant in gas generation is a potential risk to ejection application. This study performed a three-dimensional dynamic numerical simulation with Re-Normalization Group turbulence model and finite-rate/eddy-dissipation model of a two-step reaction mechanism to better understand the interaction between secondary-combustion and ring-cavity structures, and combustion effect on the loads and interior ballistic stabilization during ejection. The dynamic zone of rail cover was modelled as a rigid body, and its motion was coupled with the secondary-combustion flow in the initial chamber based on the dynamic layering method. A comparison between the numerical results and experimental data in published literature showed good agreement. Four different ring-cavity volume geometries were simulated, including no ring-cavity. Results showed that three-stage high-temperature zone can be divided in the initial chamber at the founding time in the four cases, which are a pair of spherical high-temperature zone, high-temperature zone with skirt touching walls and high-temperature zone reverse from rail cover. Additionally, increasing ring-cavity volume can accelerate the axial and radial hot gas velocity on the ring-cavity cross-section and postpone secondary-combustion process. It was also found that larger ring-cavity volume structure can smoothen the pressure and acceleration curves, reduce the out-tube-velocity and delay the out-tube-time.

Among the many retained historical information, The CPC’s archives show their unique value because of their original and authentic nature. The CPC’s history archives are used to tell the red story, spread the red culture and highlight the unique advantages of retained historical information. In the one hundred birthday of CPC, test training base in the camp salute an archives exhibition tributing to CPC centennial. The archives exhibition expands the scope of publicity, restores historical information, and highlights the role of archives in education, communication and sharing.

Water has unsurpassed capabilities in fire extinguishing. However, water scarcity is rapidly increasing in many regions and water shortage problems have led to find either new water resources or improve seawater treatment technologies. In this study, a new environment-friendly and high-efficiency powdered fire extinguishing agent with a core-shell structure is designed. The designed extinguishing agent is a colloidal powder with a 92% liquid content and is prepared through physical modification and high-speed shearing. Fumed silica is used for the external shell due to its chemical inertness, whereas seawater is used as the core due to its high extinguishing efficiency. Results show that the size of the prepared agent ranged between 100–200μm. The two fire extinguishing experiments of different scales demonstrate that the employing inorganic salts with seawater as the core can significantly increase the efficiency of the new powder in extinguishing gasoline and diesel fire compared with ultrafine and common ABC dry powders. The suppression mechanism of action is caused by the combined flame chemical and pyrolysis theories of the potassium compounds. This study would be of great theoretical significance and application value for improving the application scope of the seawater.

Data assimilation is an efficient way to improve the simulation/prediction accuracy in many fields of geosciences especially in meteorological and hydrological applications. This study takes unscented particle filter (UPF) as an example to test its performance at different two probability distribution, Gaussian and Uniform distributions with two different assimilation frequencies experiments (1) assimilating hourly in situ soil surface temperature, (2) assimilating the original Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) once per day. The numerical experiment results show that the filter performs better when increasing the assimilation frequency. In addition, UPF is efficient for improving the soil variables (e.g., soil temperature) simulation/prediction accuracy, though it is not sensitive to the probability distribution for observation error in soil temperature assimilation.

During recent years, with the drastic development of highway, lots of slopes are produced which cause the increase of geological disasters including soil erosion on the slope and shallow sliding surface, it makes significant impact on the ecological environment. Adopting ecological protection technique of plant slope protection not only can prevent geological disasters, but also benefit the protection of ecological environment. In the paper, bermuda grass, as one kind of ordinary slope protection plants, was chosen as specimen, and the root-soil composite was regarded as organic system which consists of soil and root system; the effect of root morphology on displacement of slope surface under the function of rain erosion and slope runoff erosion was studied and analyzed by using nonlinearity finite calculation method. The result indicates Bermuda grass root system can defense the rain erosion of slope surface soil, restrain the soil displacement and prevent water and soil erosion of slope.

For further research on the precondition and interoperability model of interaction ladles among continuous caster, this article takes steel ladle of Y steel works as the object of research. On the basis of turnover number calculation model of single cast steel ladle, the relationship between cast number and the turnover number and turnover times and last turnover number are further analyzed. The simulation of steel ladle turnover rules was taken on the 2 continuous casters with Gantt chart. After that, the relationships between turnover number and last turnover number and non-turnover number are researched deeply. Combining with the Gantt chart, the expressions of start casting time and empty ladle ending time and heavy ladle starting time were put forward. The precondition of steel ladle interaction is obtained, which means the exchange ladle should not undertaking transport task in first stop continuous caster, and the empty ladle end time of exchange ladle of first stop continuous caster should early than the heavy ladle start time of last stop continuous caster. After applying the model to practice, 3 steel ladles of No.2 continuous caster can be reduced. This research results is supplying theoretical basis for steel ladle controlling and production organization optimization, and enriches the theory and method of metallurgical process integration.