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Abstract Background Meat production from the commercial crossbred Duroc × (Landrace × Yorkshire) (DLY) pig is predominant in the pork industry, but its meat quality is often impaired by low ultimate pH (pHu). Muscle glycogen level at slaughter is closely associated with pHu and meat technological quality, but its genetic basis remains elusive. The aim of this study was to identify genes and/or causative mutations associated with muscle glycogen level and other meat quality traits by performing a genome-wide association study (GWAS) and additional analyses in a population of 610 DLY pigs. Results Our initial GWAS identified a genome-wide significant (P = 2.54e−11) quantitative trait locus (QTL) on SSC15 (SSC for Sus scrofa chromosome) for the level of residual glycogen and glucose (RG) in the longissimus muscle at 45 min post-mortem. Then, we demonstrated that a low-frequency (minor allele frequency = 0.014) R200Q missense mutation in the PRKAG3 (RN) gene caused this major QTL effect on RG. Moreover, we showed that the 200Q (RN –) allele was introgressed from the Hampshire breed into more than one of the parental breeds of the DLY pigs. After conditioning on R200Q, re-association analysis revealed three additional QTL for RG on SSC3 and 4, and on an unmapped scaffold (AEMK02000452.1). The SSC3 QTL was most likely caused by a splice mutation (g.8283C>A) in the PHKG1 gene that we had previously identified. Based on functional annotation, the genes TMCO1 on SSC4 and CKB on the scaffold represent promising candidate genes for the other two QTL. There were significant interaction effects of the GWAS tag SNPs at those two loci with PRKAG3 R200Q on RG. In addition, a number of common variants with potentially smaller effects on RG (P A. Conclusions We found that the RN – allele segregates in the parental lines of our DLY population and strongly influences its meat quality. Our findings also indicate that the genetic basis of RG in DLY can be mainly attributed to two major genes (PRKAG3 and PHKG1), along with many minor genes.

As an important category of urban waste, medical waste has the characteristics of polluting the environment, spreading diseases, and threatening health. It is directly related to the health of the people. The treatment of medical waste is an important part of epidemic prevention and control, and it is also a line of public health defense. This article proposes a business model that combines “C2M + multi-channel marketing” and “Internet of Things + medical” trash cans. Through market analysis, it analyzes the market situation of medical waste pretreatment link in China-medical trash can. Through the 4P marketing theory, a medical trash can be based on the Internet, which is designed mainly from the product perspective and the C2M production model is adopted; from the channel perspective, the product is first tested and sold through multiple channels. This article aims to implement the “Medical Waste Management Regulations” for the medical trash can industry and open the market to provide new ideas for reform and innovation.

In recent years, in order to adapt to the situation of rapid economic and social development, my country’s power supply companies have invested large-scale funds to build distribution networks, and upgraded urban and rural power grids, effectively supporting the rapid growth of power demand and the reliability of power supply. Continuous improvement of power quality. While the scale of investment in the distribution network continues to remain high, problems such as focusing on investment and neglecting revenue, focusing on project establishment and neglecting management also exist to varying degrees. Therefore, reasonably predicting the scale of investment in the distribution network and improving the lean management level of the investment and construction of the distribution network have become key issues that power supply companies need to solve. This paper takes my country’s municipal power supply companies as the research object, combines the actual business development of the company’s distribution network investment planning, and fully considers the impact of the company’s power supply district management and the level of cost differences on the investment scale of the distribution network, and builds a fit on this basis. The distribution network investment planning forecast model of the actual business work of the enterprise guides the municipal power supply enterprises to improve the lean management level of the distribution network investment and construction.

Daya Bay Nuclear Power Plant has been running for above 20 years. main condensers have begun to run during the commissioning phase before the official commercial operation, so it is imminent to carry out the life cycle management of main condensers combined with demonstration of the operation license extended to 60 years. A life cycle management system for main condensers in nuclear power plant is established in this paper, which is applied to management practices of Daya Bay Nuclear Power Plant.

China has issued eight mandatory national standards so far to regulate the water efficiency of household products. The State Administration for Market Regulation performs national spot checks yearly on products qualities, which includes water efficiency, meantime it required market regulation bureaucracies of regional levels to strengthen inspection of energy and water efficiency labels from 2019. However, those two levels of inspection neither focus on water efficiency standards nor cover all eight categories of products. Furthermore, there is still space to improve in term of supervision effectiveness, efficiency and database management. For those reasons, this article aims to clarify the deficiencies and propose corresponding advice on the supervision system.

The initial design life of nuclear power plant is 40 years. In 60 year life extending license application, the fatigue of component should be evaluated under the influence of the fatigue factors of the pressurized water reactor coolant environment. Because the original design used a more conservative analysis method, the result could not meet the requirement of Cumulative usage fatigue factor of RCC-M. An optimizing analysis method is studied, and as an example of application, optimizing fatigue analysis of Safety Injection Nozzle of Main Coolant Line is performed. The evaluation results show that the optimized fatigue analysis results meet the requirements of RCC-M.

Detennining the constitutive model is a key procedure in numerical simulation of concrete structures. The uniaxial stress-strain curve is important information to determine the concrete constitutive model. This paper provided a simplified stress-strain curve of concrete that can be used in simulation. The comparison between Chinese Code and the simplified curve shows that the simplified curve of uniaxial compression is close to the code value. Numerical simulation of concrete beams show that the simplified curve proposed has high computational efficiency and good convergence.