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The Danish fire loss dataset records commercial fire losses under three insurance coverages: building, contents, and profits. Existing research has primarily focused on the heavy-tail behaviour of the losses but ignored the relationship among different insurance coverages. In this paper, we aim to model the aggregate loss for all three coverages. To study the pairwise dependence of claims from all types of coverage, an independent model, a hierarchical model, and some copula-based models are proposed for the frequency component. Meanwhile, we applied composite distributions to capture the heavy-tailed severity component. It is shown that consideration of dependence for the multi-peril frequencies (i) significantly enhances model goodness-of-fit and (ii) provides more accurate risk measures of the aggregated losses for all types of coverage in total. [ABSTRACT FROM AUTHOR]

In view of the problems of high production cost, scarcity and lack of diversity of 3D face datasets, this paper designs an end-to-end self-supervised learning 3D face reconstruction algorithm with a single 2D face image as input, which only uses 2D face datasets to complete model training. First, the improved ResNet module is introduced to preprocess the input face image. The deep residual neural network has strong feature extraction and characterization ability for the image, which can provide rich high-level semantic feature maps for the subsequent subnetwork. Then, add transformer module completely based on self-attention mechanism to the parameter prediction subnetwork, which can make different parameters of the subnetwork focus on self-related feature map information and avoid interference from invalid feature map information, so as to further improve the parameter prediction accuracy of the subnetwork. Next, training, ablation and comparison experiments were conducted on CelebA, BFM and Photoface datasets, and the combined function of pixel loss function and perceptual loss function was selected as the loss function. The experimental results show that: compared with the historical optimal results of the same network structure, the scale-invariant depth error (SIDE) and mean angle deviation (MAD) are improved by 5.9% and 10.8%, respectively, which strongly proves the effectiveness of the algorithm. Finally, in order to verify the actual effect of the 3D face reconstruction algorithm, examples are selected in this paper for reconstruction. The 3D faces generated by the algorithm all have a good sense of reality, which intuitively and effectively proves the advancement of the algorithm. [ABSTRACT FROM AUTHOR]

Simple Summary: We developed the DAS–ELISA to investigate the infection and prevalence of GyH1 in chickens and wild birds in China. We found that natural GyH1 infections were widespread in chickens and wild birds. Importantly, young chickens are more susceptible to GyH1, and local chicken species in China are genetically resistant to GyH1. In particular, we found a significantly higher GyH1–positive rate in wild birds than in chickens, implying that there may be a risk of GyH1 transmission from wild birds to chickens. Gyrovirus homsa1 (GyH1) is an emerging pathogenic single–stranded circular DNA virus that leads to immunosuppression, aplastic anemia, and multisystem damage in chickens. However, the prevalence of GyH1 infection in chickens and wild birds remains unknown. Here, we developed a double–antibody sandwich enzyme–linked immunosorbent assay (DAS–ELISA) to investigate GyH1 infection in 8 chicken species and 25 wild bird species. A total of 2258 serum samples from chickens (n = 2192) in 15 provinces, and wild birds (n = 66) in Jinan Wildlife Hospital were collected from 2017 to 2021 in China. The GyH1–positive rates in chickens and wild birds were 9.3% (203/2192) and 22.7% (15/66), respectively. GyH1 was present in all flocks in 15 provinces. From 2017 to 2021, the positive rate ranged from 7.93% (18/227) to 10.67% (56/525), and the highest positive rate was present in 2019. Upon chicken age, the highest positive rate (25.5%) was present in young chickens (14–35 days old). Moreover, the GyH1–positive rate in broiler breeders (12.6%, 21/167) was significantly higher than that in layer chickens (8.9%, 14/157). This study shows that GyH1 has spread in chicken flocks and wild birds, and the higher GyH1–positive rate in wild birds indicates the risk of spillover from wild birds to chickens. Our study expanded the GyH1 epidemiological aspects and provided a theoretical basis for GyH1 prevention. [ABSTRACT FROM AUTHOR]

Chicken anemia virus (CAV) and Gyrovirus homsa 1 (GyH1) are members of the Gyrovirus genus. The two viruses cause similar clinical manifestations in chickens, aplastic anemia and immunosuppression. Our previous investigation displays that CAV and GyH1 often co-infect chickens. However, whether they have synergistic pathogenicity in chickens remains elusive. Here, we established a co-infection model of CAV and GyH1 in specific pathogen-free (SPF) chickens to explore the synergy between CAV and GyH1. We discovered that CAV and GyH1 significantly inhibited weight gain, increased mortality, and hindered erythropoiesis in co-infected chickens. Co-infected chickens exhibited severe immune organ atrophy and lymphocyte exhaustion. The proventriculus and gizzard had severe hemorrhagic necrosis and inflammation. We also discovered that the viral loads and shedding levels were higher and lasted longer in CAV and GyH1 co-infected chickens than in mono-infected chickens. Our results demonstrate that CAV and GyH1 synergistically promote immunosuppression, pathogenicity, and viral replication in co-infected chicken, highlighting the interaction between CAV and GyH1 in the disease process and increasing potential health risk in the poultry breeding industry, and needs further attention. [ABSTRACT FROM AUTHOR]

The midpalatal suture is mainly responsible for the growth and development of the maxillary and resistance to rapid maxillary expansion (RME). It is essential for clinical researchers to explore the intramembrane ossification and to elucidate the underlying mechanism of the maturation and ossification process of the midpalatal suture to help identify the optimum time and force of RME. However, mechanistic studies associated with the midpalatal suture are rare. The aim of this present study is to create an intramembrane osteogenesis model for the midpalatal suture region of mice. Interestingly, we discovered a type of chondrogenic mesenchymal cell expressing Piezo2, which might be related to the detection of mechanical and external stimuli. This result provides a potential molecular and cellular mechanism that explains why the midpalatal suture is not closed until adulthood. We depict a landscape of mesenchymal cells that might play an important role in the intramembrane osteogenesis of the midpalatal suture and provide new perspectives on midpalate suture maturation and ossification, which might lead to further possibilities for clinical operations. [ABSTRACT FROM AUTHOR]

• GyV3 induced persistent infection in both chickens and mice. • Bone marrow and cerebrum are GyV3 targets in chickens and mice. • Genetic diversity analysis showed that GyV3 can adapt to new hosts. • Adaptation occurs via rapid evolution in the hypervariable region of VP1. Gyrovirus 3 (GyV3) has been identified in humans and other hosts, suggesting its cross-species pathogenicity, which poses an increased public health risk. In the current study, we established chicken and mouse models of GyV3 infection. We found that GyV3 induced persistent infections, characterized by viremia, aplastic anemia, immunosuppression, and systematic lymphocytic inflammation, in both species. Kinetic viral loads and antigen expression demonstrated rapid viral replication and broad tissue tropism of GyV3 in both models. The highest viral loads and the strongest antigen immunostaining were present in bone marrow and cerebrum in both chickens and mice, indicating that these are target tissues for GyV3. Genetic diversity analysis of VP1 in infected chickens and mice showed that GyV3 adapts to new hosts via rapid evolution of the hypervariable region of the gene encoding the structural protein VP1. Overall, our results indicate that GyV3 is a cross-species pathogenic virus; therefore, more attention needs to be paid to high levels of GyV3-induced neurotropism and aplastic anemia as a public health risk. [ABSTRACT FROM AUTHOR]