Expression, localization, and function of P4HB in the spermatogenesis of Chinese mitten crab (Eriocheir sinensis)

Background The sperm of Chinese mitten crab (Eriocheir sinensis) have special noncondensed nuclei. The formation and stability of the special nuclei are closely related to the correct folding of proteins during spermatogenesis. P4HB plays a key role in protein folding, but its expression and role in the spermatogenesis of E. sinensis are unclear. Objective To investigate the expression and distribution characteristics of P4HB in the spermatogenesis of E. sinensis as well as its possible role. Methods The testis tissues of adult and juvenile E. sinensis were used as materials. We utilized a variety of techniques, including homology modeling, phylogenetic analysis, RT-qPCR, western blotting, and immunofluorescence staining to predict the protein structure and sequence homology of P4HB, analyze its expression in the testis tissues, and localize and semi-quantitatively assess its expression in different male germ cells. Results The sequence of P4HB protein in E. sinensis shared a high similarity of 58.09% with the human protein disulfide isomerase, and the phylogenetic tree analysis indicated that the protein sequence was highly conserved among crustaceans, arthropods, and other animals species. P4HB was found to be expressed in both juvenile and adult E. sinensis testis tissues, with different localization patterns observed all over the developmental stages of male germ cells. It was higher expressed in the spermatogonia, spermatocytes, and stage I spermatids, followed by the mature sperm than in the stage II and III spermatids. The subcellular localization analysis revealed that P4HB was predominantly expressed in the cytoplasm, cell membrane, and extracellular matrix in the spermatogonia, spermatocytes, stage I and stage II spermatids, with some present in specific regions of the nuclei in the spermatogonia. In contrast, P4HB was mainly localized in the nuclei of stage III spermatids and sperm, with little expression observed in the cytoplasm. Conclusion P4HB was expressed in the testis tissues of both adult and juvenile E. sinensis, but the expression and localization were different in male germ cells at various developmental stages. The observed differences in the expression and localization of P4HB may be an essential factor in maintaining the cell morphology and structure of diverse male germ cells in E. sinensis. Additionally, P4HB expressed in the nuclei of spermatogonia, late spermatids, and sperm may play an indispensable role in maintaining the stability of the noncondensed spermatozoal nuclei in E. sinensis

Design and Preparation of Flexible Graphene/Nonwoven Composites with Simultaneous Broadband Absorption and Stable Properties

As the world moves into the 21st century, the complex electromagnetic wave environment is receiving widespread attention due to its impact on human health, suggesting the critical importance of wearable absorbing materials. In this paper, graphene nonwoven (RGO/NW) composites were prepared by diffusely distributing graphene sheets in a polypropylene three-dimensional framework through Hummers’ method. Moreover, based on the Jaumann structural material design concept, the RGO/NW composite was designed as a multilayer microwave absorber, with self-recovery capability. It achieves effective absorption (reflection loss of −10 dB) in the 2~18 GHz electromagnetic wave frequency domain, exhibiting a larger bandwidth than that reported in the literature for absorbers of equivalent thickness. In addition, the rationally designed three-layer sample has an electromagnetic wave absorption of over 97% (reflection loss of −15 dB) of the bandwidth over 14 GHz. In addition, due to the physical and chemical stability of graphene and the deformation recovery ability of nonwoven fabric, the absorber also shows good deformation recovery ability and stable absorption performance. This broadband absorption and extreme environmental adaptability make this flexible absorber promising for various applications, especially for personnel wearable devices

Design and Preparation of Flexible Graphene/Nonwoven Composites with Simultaneous Broadband Absorption and Stable Properties

As the world moves into the 21st century, the complex electromagnetic wave environment is receiving widespread attention due to its impact on human health, suggesting the critical importance of wearable absorbing materials. In this paper, graphene nonwoven (RGO/NW) composites were prepared by diffusely distributing graphene sheets in a polypropylene three-dimensional framework through Hummers’ method. Moreover, based on the Jaumann structural material design concept, the RGO/NW composite was designed as a multilayer microwave absorber, with self-recovery capability. It achieves effective absorption (reflection loss of −10 dB) in the 2~18 GHz electromagnetic wave frequency domain, exhibiting a larger bandwidth than that reported in the literature for absorbers of equivalent thickness. In addition, the rationally designed three-layer sample has an electromagnetic wave absorption of over 97% (reflection loss of −15 dB) of the bandwidth over 14 GHz. In addition, due to the physical and chemical stability of graphene and the deformation recovery ability of nonwoven fabric, the absorber also shows good deformation recovery ability and stable absorption performance. This broadband absorption and extreme environmental adaptability make this flexible absorber promising for various applications, especially for personnel wearable devices

Absorbing property of MnO2 nanorods and its meta-surface design

MnO2 nanorods were prepared by using the hydrothermal method and freeze-drying technology, and then molded into the MnO2/paraffin circular samples in different filling concentrations. The crystalline phase, microstructure and electromagnetic parameters of the samples were characterized and tested by X-ray diffractometer (XRD), scanning electron microscopy (SEM), and vector network analyzer (VNA). Sample meta-surface was designed and simulated by CST software and the pre and post simulation calculation and research of the meta-surface were carried out. The results show that prepared MnO2 powder has a rod structure with the diameter and length of the rod about 50-100 nm, 5-10 μm, respectively. The single cylindric structure is well-shaped, and the overall structure is homogeneous with crystallinity. Moreover, the tangent of dielectric loss(tanδ) increases with concentration, making a great contribution to the electromagnetic attenuation coefficient (α) of the sample of MnO2/paraffin, which increases with filling concentration of MnO2 nanorods. Microwave absorption frequency domain of MnO2/paraffin material is significantly broadened by the design of meta-surface, namely, the optimal bandwidth in 2-18 GHz can reach 14.32 GHz. The reason is the superposition of absorption peaks over a specified frequency range, which is caused by the coexistence of multiple resonances of the meta-surface

Effects of Fermented Tea Residue on Fattening Performance, Meat Quality, Digestive Performance, Serum Antioxidant Capacity, and Intestinal Morphology in Fatteners

This study investigated the dietary supplementation of tea residue fermented by Bacillus subtilis, Aspergillus niger, and Saccharomyces cerevisiae, to explore its effects on growth performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology in pigs bred for rapid growth, also known as fatteners. One hundred and ninety-two healthy “Duroc × Landrace × Yorkshire” ternary hybrid pigs (body weight 70 ± 1.0 kg) were randomly divided into four groups according to the feeding test requirements, with four replicates in each group, and 12 fatteners per replicate. The control group (CG) was fed the basal diet. Treatments 1 (T1), 2 (T2), and 3 (T3), comprising ratios of 10%, 15%, and 20% of tea residue were added to the basal diet. The test period was 60 days. The results showed that supplementation of FTR in fatteners’ diets increased final body weight (FBW), average daily gain (ADG), and feed conversion ratio (FCR) in the T1 and T2 groups (p < 0.05). Compared with the other groups, the lightness (L*) and pH were significantly affected in the T2 group (p < 0.05). Compared with the CG, dietary supplementation of FTR significantly increased the nutrient digestibility of crude protein (CP), ether extract (EE), calcium (Ca), and phosphorus (P), improved the lipase and trypsin activities, and reduced drip loss and the shear force of fatteners (p < 0.05). Glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) were significantly increased in the T2 and T3 groups compared with the other groups (p < 0.05). Supplementation of FTR in the jejunum significantly increased the villi height of the T2 group and the ratio of villi height to crypt depth of the FTR groups. Compared with the other two groups, the T2 and T3 groups significantly reduced the ratio of the villous height to crypt depth in the duodenum (p < 0.05). In conclusion, the tea residue after fermentation was shown to have beneficial effects on the fattening performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology of fatteners