Association Between Intergenerational Support, Social Integration, and Subjective Well-Being Among Migrant Elderly Following Children in Jinan, China.

Background: In China, as domestic urbanization progresses and immigration expands, an increasing number of older people are choosing to follow their migrant children to new cities. Such people are referred to as "migrant elderly following children." However, few studies have explored the subjective well-being of these older adults. The present study aims to investigate the factors that influence the subjective well-being of this population of older adults. Methods: This cross-sectional study was conducted among 656 older migrants who had followed their children to Jinan, Shandong Province, China. Multistage cluster random sampling was used. Binary logistic regression analyses were performed to explore, the relationships between intergenerational support, social integration, and subjective well-being. Results: Overall, 96.3% of the older migrants showed good subjective well-being. Analysis of intergenerational support showed that those who had a female child (odds ratio [OR] = 0.401, 95% confidence interval [95%CI]: 0.180, 0.893) and those whose children had terrible conjugal relationships (OR = 0.223, 95% CI: 0.099, 0.504) were less likely to have better subjective well-being. Analysis of social integration showed that migrants who liked their current city (OR = 5.358, 95%CI: 1. 631, 17.599) and those who had a basic understanding of the local dialect (OR = 2.869, 95%CI: 1.203, 6.843) were more likely to have good subjective well-being. Migrants who had used in-patient service in the past year (OR = 0.216, 95%CI: 0.094, 0.497) were more likely to have poor subjective well-being. Conclusion: Intergenerational support and social integration are positively associated with the subjective well-being of migrant elderly following children in China. Efforts should be made, including the creation of specialized policies, to improve the family atmosphere of such migrants and their integration into their new cities, as this would contribute to improving their subjective well-being.

A specific primed immune response in red palm weevil, Rhynchophorus ferrugineus, is mediated by hemocyte differentiation and phagocytosis.

Red palm weevil, Rhynchophorus ferrugineus, is an invasive and destructive pest that causes serious damages to palm trees. Like other invertebrates, red palm weevil relies solely on its innate immune response to fight invading microbes; by definition, innate immunity lacks adaptive characteristics. However, we show here that priming the red palm weevil larvae with heat-killed Bacillus thuringiensis specifically increased survival of the larvae during a secondary lethal infection with live bacteria, and B. thuringiensis primed larvae also showed a higher clearance efficiency for this bacterium, which indicated that the red palm weevil larvae possessed a strong immune priming response. The degree of enhanced immune protection was positively correlated with hemocyte proliferation and the level of phagocytic ability of hemocytes. Moreover, the red palm weevil larvae primed by B. thuringiensis induced the continuous synthesis of serotonin in the hemolymph, which in turn enhanced the phagocytic ability and pathogen clearance ability of the host, representing an important mechanism for the red palm weevil to achieve priming protection. Our findings reveal a specific immune priming of the red palm weevil larvae mediated by the continuous secretion of serotonin, and provide new insights into the mechanisms of invertebrates immune priming.

Non-palm Plant Volatile α-Pinene Is Detected by Antenna-Biased Expressed Odorant Receptor 6 in the Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae).

The majority of insects rely on a highly complex and precise olfactory system to detect various volatile organic compounds released by host and non-host plants in environments. The odorant receptors (ORs) are considered to play an important role in odor recognition and the molecular basis of ORs, particularly in coleopterans they are relatively poorly understood. The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae), is one of the most destructive pests of the global palm industry. Although feeding and egg oviposition behaviors of RPW can be repelled by some non-palm plant volatiles, such as α-pinene, geraniol, or 1-octen-3-ol, there is limited understanding of how RPW recognizes the non-host plant volatiles. In this study, three candidate RferOrs were identified from the Rfer-specific clade, and the tissue expression analysis used was mainly expressed in the antennae of both sexes. Functional characterization of RferOr6, RferOr40, and RferOr87 was analyzed by using the Xenopus oocyte expression system, and the results indicated that RferOr6/RferOrco was narrowly tuned to α-pinene. The behavioral experiment showed that α-pinene at the concentrations of 10 and 100 µg/µl can cause a significantly repelled behavioral response of RPW. In conclusion, this study reveals that RferOr6 is an antenna-biased expressed OR used by RPW to detect the volatile compound α-pinene in non-palm plants, and our results provide a foundation for further in vivo functional studies of Or6 in RPW, including in vivo knockout/knockdown and feeding/ovipositing behavioral studies of RPW and further pest control.

Variation in Parasitoid Virulence of Tetrastichus brontispae during the Targeting of Two Host Beetles.

In host-parasitoid interactions, antagonistic relationship drives parasitoids to vary in virulence in facing different hosts, which makes these systems excellent models for stress-induced evolutionary studies. Venom compositions varied between two strains of Tetrastichus brontispae, Tb-Bl and Tb-On. Tb-Bl targets Brontispa longissima pupae as hosts, and Tb-On is a sub-population of Tb-Bl, which has been experimentally adapted to a new host, Octodonta nipae. Aiming to examine variation in parasitoid virulence of the two strains toward two hosts, we used reciprocal injection experiments to compare effect of venom/ovarian fluids from the two strains on cytotoxicity, inhibition of immunity and fat body lysis of the two hosts. We found that Tb-Onvenom was more virulent towards plasmatocyte spreading, granulocyte function and phenoloxidase activity than Tb-Blvenom. Tb-Blovary was able to suppress encapsulation and phagocytosis in both hosts; however, Tb-Onovary inhibition targeted only B. longissima. Our data suggest that the venom undergoes rapid evolution when facing different hosts, and that the wasp has good evolutionary plasticity.