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A combined three-source estimator is used to estimate the net error rate of population size in household registration. It avoids the bias in the two-source estimator due to the fact that the registration of an individual on one list affects his or her registration on another list. It makes better use of frequencies than the ordinary three-source estimator. It yields an estimated net error rate that is closest to 1% of error. The combined three-source estimator combines missing-cell estimators of ordinary three-source estimators working on the contingency table of presence or absence in the census population list, the post-enumeration survey population list, and the household population list. Matching of these three registration lists is filled into the seven non-missing cells of the contingency table. The missing-cell estimator involved in the combined three-source estimator is based on the missing-cell estimators of the ordinary three-source estimators. It requires that the three population lists fully register the post-strata population. In the case of sample registration, it is based on the sampling weights and population sizes of the sampled small census areas. It provides a lower mean square error than the ordinary three-source estimator, which itself provides a lower mean square error than the two-source estimator. The estimated 0.96% net under-registration rate of population size for the country as a whole in household registration is close to the 1.00% rate found in the rectification of household registration carried out by China's Ministry of Public Security between May 15, 2010, and September 30, 2010. Despite the bias coming from the residual heterogeneity of individuals in each post-stratum, as the sample can only accommodate a limited total number of post-strata, the combined three-source estimator should yield a smaller mean square error than the ordinary three-source estimator of the net error rate of population size in household registration. [ABSTRACT FROM AUTHOR]

Breeding pigeons is a fundamental source of profit in various enterprises but little is known on the metabolic laws governing their lactation. In this study, we analysed the metabolic profile of different sex of breeding pigeons (Columba livia, European pigeons, Mimas) during lactation. We found that male pigeons exhibited catabolism during lactation. Extension of lactation resulted in increased weight loss, then slow recovery of body weight. Conversely, the weight loss in female pigeons peaked on the seventh day of lactation. They then gradually recovered their body weight. Male pigeons showed more duration of combing, while female pigeons showed more duration of resting. In male pigeons, except for triglyceride (TG), which increased, blood lipid indexes barely changed during lactation. Conversely, in females, both TG and total cholesterol increased in middle and late lactation. The level of oxidative stress in female pigeons during lactation was higher than in males, lipid peroxide malondialdehyde, hydrogen peroxide (H2O2), plasma calcium (Ca) and phosphorus (P) levels increased in late lactation. Levels of estradiol and progesterone in female pigeons increased during lactation, whereas those of luteotropic hormone (LH), follicle‐stimulating hormone (FSH), prolactin (PRL) and testosterone gradually decreased. As per LC‐MS spectra analysis, the differential metabolites in the plasma on the day of hatching and before laying in female pigeons in lactation were enriched in retrograde endocannabinoid signalling, α‐linolenic acid, arachidonic acid, choline, glycerophospholipid metabolisms, and valine, leucine, and isoleucine degradations. Levels of fatty acids, amino acids, sphingomyelin and phosphatidylinositol related to the secretion of pigeon milk had reduced, whereas the levels of phosphatidylcholine, phosphatidylethanolamine, and TG, which are all related to egg production, had increased. In conclusion, our study systematically revealed the different metabolic characteristics of male and female breeding pigeons during lactation. This is useful for precision feeding of pigeons and applicable in nutritional interventions for improved production. [ABSTRACT FROM AUTHOR]

We studied the dynamic stiffness, strain energy density, and fatigue life of phenyl silicone rubber at - 40 - 20 t, and verified the consistency between the experimental results and the fatigue life calculation formula based on crack growth theory. The results show that when the temperature increases, the phenyl silicone rubber decreases its dynamic stiffness and strain energy density, but increases the fatigue life, whose characteristics meet the prediction model of the fatigue life. [ABSTRACT FROM AUTHOR]

The research progress of heat resistance, cold resistance, electrical conductivity and damping properties of aviation silicone rubber were reviewed in this article. The heat resistance properties of silicone rubber can be enhanced by changing the molecular structure (main chain, end-group, side chain and molecular weight) of the gum and adding special heat-resistance filler. The cold resistance of aviation silicone rubber can be enhanced by adjusting the side chain molecular structure of the gum and the content of different gum chain. The electrical conductivity of silicone rubber can be improved by optimizing, blending and dispersing of conductive particles. The damping property of silicone rubber can be improved by designing and synthesizing of high-molecular polysiloxane damping agent. Furthermore, the application of aviation silicone rubber used in high-low temperature seal, electrical conduction and vibration damping technology are also summarized, and the high performance (for example long-term high temperature resistance, ultralow temperature resistance, high electromagnetic shelding, long-term fatigue resistance vibration damping, quasi constant modulus and so on) of special silicone rubber is the future direction of aviation silicone rubber.

This study evaluated the effect of Lentinus edodes fermentation (LEF) on digestive enzyme activity, antioxidant capacity and morphology of the liver and intestine in largemouth bass (Micropterus salmoides) fed high plant protein diets (HPPD). LEF was supplemented in HPPD with 0 g kg−1 (LEF0), 10 g kg−1 (LEF1), 20 g kg−1 (LEF2), 30 g kg−1 (LEF3), 40 g kg−1 (LEF4), 50 g kg−1 (LEF5), respectively, and then the six diets were fed to largemouth bass with a body weight of 28.8 ± 0.05 g for eight weeks. Juvenile fish were randomized into 6 groups and each group had 4 replicates with 40 fish. Dietary LEF supplementation alleviated the liver inflammatory reaction of largemouth bass caused by HPPD and improved liver morphology. Goblet cells multiplied and the gut muscle layer thickened after LEF supplementation. The LEF significantly increased amylase activity in the liver and intestine of largemouth bass in individual experimental groups. The LEF could increase the activity of catalase in the liver and intestine of largemouth bass (p < 0.05). The content of malondialdehyde was significantly lower than that in the control group (p < 0.05). Dietary LEF supplementation had no significant effect on the intestinal flora of largemouth bass. These findings imply that LEF supplementation can reduce liver inflammation, enhance intestinal tissue morphology, and eventually benefit largemouth bass health. [ABSTRACT FROM AUTHOR]