In the study, papain was chosen from five proteases to hydrolyze proteins of monkfish swim bladders for effectively utilizing monkfish (
) processing byproducts, and the hydrolysis conditions of ...papain were optimized as hydrolysis temperature of 65 °C, pH 7.5, enzyme dose 2.5% and time 5 h using single-factor and orthogonal experiments. Eighteen peptides were purified from the swim bladder hydrolysate of monkfish by ultrafiltration and gel permeation chromatography methods and identified as YDYD, QDYD, AGPAS, GPGPHGPSGP, GPK, HRE, GRW, ARW, GPTE, DDGGK, IGPAS, AKPAT, YPAGP, DPT, FPGPT, GPGPT, GPT and DPAGP, respectively. Among eighteen peptides, GRW and ARW showed significant DPPH· scavenging activities with EC
values of 1.053 ± 0.003 and 0.773 ± 0.003 mg/mL, respectively; YDYD, QDYD, GRW, ARW and YPAGP revealed significantly HO· scavenging activities with EC
values of 0.150 ± 0.060, 0.177 ± 0.035, 0.201 ± 0.013, 0.183 ± 0.0016 and 0.190 ± 0.010 mg/mL, respectively; YDYD, QDYD, ARW, DDGGK and YPAGP have significantly O2-· scavenging capability with EC
values of 0.126 ± 0.0005, 0.112 ± 0.0028, 0.127 ± 0.0002, 0.128 ± 0.0018 and 0.107 ± 0.0002 mg/mL, respectively; and YDYD, QDYD and YPAGP showed strong ABTS
· scavenging ability with EC
values of 3.197 ± 0.036, 2.337 ± 0.016 and 3.839 ± 0.102 mg/mL, respectively. YDYD, ARW and DDGGK displayed the remarkable ability of lipid peroxidation inhibition and Ferric-reducing antioxidant properties. Moreover, YDYD and ARW can protect Plasmid DNA and HepG2 cells against H
O
-induced oxidative stress. Furthermore, eighteen isolated peptides had high stability under temperatures ranging from 25-100 °C; YDYD, QDYD, GRW and ARW were more sensitive to alkali treatment, but DDGGK and YPAGP were more sensitive to acid treatment; and YDYD showed strong stability treated with simulated GI digestion. Therefore, the prepared antioxidant peptides, especially YDYD, QDYD, GRW, ARW, DDGGK and YPAGP from monkfish swim bladders could serve as functional components applied in health-promoting products because of their high-antioxidant functions.
Minimal models of active Brownian colloids consisting of self-propelled spherical particles with purely repulsive interactions have recently been identified as excellent quantitative testing grounds ...for theories of active matter and have been the subject of extensive numerical and analytical investigation. These systems do not exhibit aligned or flocking states but do have a rich phase diagram, forming active gases, liquids, and solids with novel mechanical properties. This article reviews recent advances in the understanding of such models, including the description of the active gas and its swim pressure, the motility-induced phase separation and the high-density crystalline and glassy behavior.
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•Describe minimal model of active colloids.•Discuss the behavior of active gasses, emphasizing the role of stress and, in particular, of the swim pressure.•Discuss the motility-induced phase separation in active fluids.•Discuss the physics of active glasses and active solids and their jamming dynamics.
•Near-eye display system with large field of view and large pupil is often accompanied by field curvature. In this paper, the system is modeled, and the curvature is controlled through optimization ...based on the effects of various aberrations. Under limited conditions, the field curvature of the system is controlled to the ideal state.•Based on the focusing function of human eye, the image quality of the system with curved image is evaluated and optimized. At the same time, the field curvature and pupil swim were analyzed jointly. The effectiveness of the method is verified by designing two different types of near-eye display systems.•The article provides two optimization strategies for near-eye display systems: one prioritizes minimizing field curvature, while the other focuses on optimizing image quality. These strategies are suitable for different systems. However, these two optimization methods are not isolated; they can be combined to balance various system metrics.
Near-eye display (NED) systems with a large field of view (FOV) and a large pupil are often accompanied by field curvature. In such cases, there is often a significant deviation between the virtual image seen by the human eye and an ideal plane. Currently, there is a lack of precise methods for describing and controlling the shape of virtual images in visual space. In this paper, the system is modeled, and the curvature is controlled through optimization. Under limited conditions, the system’s field curvature is controlled to approach an ideal state. When the system’s field curvature cannot be completely corrected, a method for describing the virtual image surface is introduced. This method helps optical designers effectively predict the degree of curvature and the distance of the virtual image. The image quality of the system with a curved image is evaluated and optimized based on the focusing function of the human eye. Additionally, the field curvature and pupil swim are analyzed jointly. The effectiveness of the method is verified by designing two different types of NED systems.
The forced swim test (FST) and tail suspension test (TST) are widely used to assess depressive-like behaviors in animals. Immobility time is used as an important parameter in both FST and TST. ...Traditional methods for analyzing FST and TST rely on manually setting the threshold for immobility, which is time-consuming and subjective.
We proposed a threshold-free method for automated analysis of mice in these tests using a Dual-Stream Activity Analysis Network (DSAAN). Specifically, this network extracted spatial information of mice using a limited number of video frames and combined it with temporal information extracted from differential feature maps to determine the mouse’s state. To do so, we developed the Mouse FSTST dataset, which consisted of annotated video recordings of FST and TST.
By using DSAAN methods, we identify immobility states at accuracies of 92.51 % and 88.70 % for the TST and FST, respectively. The predicted immobility time from DSAAN is nicely correlated with a manual score, which indicates the reliability of the proposed method. Importantly, the DSAAN achieved over 80 % accuracy for both FST and TST by utilizing only 94 annotated images, suggesting that even a very limited training dataset can yield good performance in our model.
Compared with DBscorer and EthoVision XT, our method exhibits the highest Pearson correlation coefficient with manual annotation results on the Mouse FSTST dataset.
We established a powerful tool for analyzing depressive-like behavior independent of threshold, which is capable of freeing users from time-consuming manual analysis.
•A dual-stream framework-DSAAN is proposed for automatic behavior analysis.•DSAAN precisely predicts the immobility time of FST and TST in mice.•DSAAN is capable of freeing users from time-consuming manual analysis.
The swim bladder colloid (SWG) was prepared by the swim bladder (SW) from Atlantic cod (Gadus Morhua), and its physicochemical, rheological and digestive properties were evaluated. It showed SW ...mainly consisted of collagens and chondroitin sulfate. The optimal condition of SWG was treated with acetic acid for 4.0 h, operated with high temperature and pressure time for 30 min and homogenized twice at 100 MPa pressure. The viscosity of SWG, containing the mixed system of proteins and polysaccharides, decreased with the increasing of shear rate, exhibiting shear thinning behavior, which conformed to pseudoplastic fluid. It demonstrated larger values for G″ than that for G′ at the frequency of 20 Hz at 25 °C, which reached 30.8 Pa and 5.15 Pa at 60% concentration, respectively. Moreover, when the concentrations increased from 20% to 80%, the gelation temperatures and the melting temperatures increased from 6.79 ± 0.01 °C and 12.61 ± 0.06 °C to 13.73 ± 0.06 °C and 18.31 ± 0.05 °C, respectively. All of G''/G′ were much less than 0.1, confirming the presence of solid-like elastic behavior at 4.0 °C. When the temperature increased from 40 °C to 85 °C, the viscosity at 20% concentration of SWG decreased from 34.50 mPa s to 8.07 mPa s at the shear rate of 100 s−1. Furthermore, it exhibited that SWG was digested and degraded after simulated digestion in vitro, and bioactive peptides were produced.
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•The swim bladder was mainly composed of collagen and chondroitin sulfate.•The preparation of swim bladder colloid (SWG) was optimized.•High concentrations of SWG increased the intermolecular forces.•SWG at low temperatures exhibited solid-like elastic behaviors.•SWG was sensitive to digestion in vitro.
•DEHP and DEHA affected the expression of thyroid-related genes in Japanese medaka•DEHP and DEHA decreased medaka eye size and total body length•DEHA reduced swim bladder inflation•DEHP and DEHA did ...not affect medaka swimming performance•DEHP in tap water in Kobe, Japan may disrupt medaka thyroid hormone activity
Pollution of water bodies with plasticizers is a serious environmental problem worldwide. In this study, we investigated the effects of plasticizers bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka (Oryzias latipes). DEHP significantly increased the expression of all the genes tested: thyroid stimulating hormone beta subunit (tshβ-like), tshβ, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trβ). However, DEHA only significantly increased tshβ at 7.4 µg/L but significantly decreased dio2 expression at 25.8, 111.1, and 412.6 4 µg/L, while other genes were not significantly affected. Both chemicals reduced eye size and total body length, but did not affect embryo development, hatching time and rate, and swimming performance. DEHA alone affected swim bladder inflation and not DEHP. This is the first report that not only DEHP but also DEHA disrupt thyroid hormone activity in fish. DEHP contamination (13.2 μg/L) was detected in tap water from Kobe, Japan; thus, tap water itself may disrupt thyroid hormone activity in Japanese medaka. Importantly, the effective concentration of DEHP for thyroid hormone–related gene expression and growth was close to or lower than DEHP concentrations reported in surface water elsewhere, indicating that DEHP contamination is a serious aquatic pollution.
Thyroid-hormone-disrupting chemicals are increasingly attracting attention because of their potential harmful effects on animal health, including on fishes. Here, we investigated the effects of ...exposure to the thyroid-hormone-disrupting chemicals 6-propyl-2-thiouracil (PTU) and tetrabromobisphenol A (TBBPA) on swim bladder inflation, eye development, growth, swimming performance, and the expression of thyroid-related genes in Japanese medaka (Oryzias latipes). PTU exposure resulted in reductions in eye size, growth, and swim bladder inflation, and these effects led to poorer swimming performance. These phenotypic effects were accompanied by increased expression of the thyroid-stimulating hormone subunit beta (tshβ) paralog tshβ-like, but there were no significant changes in expression for tshβ, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trβ). For PTU exposure, we identified the key event (swim bladder inflation reduction) and an adverse outcome (swimming performance reduction). No significant effects from TBBPA exposure were seen on swim bladder inflation, eye development, growth, or swimming performance. However, expression of tshβ-like and tshβ (significantly enhanced) and trα and trβ (significantly reduced) were affected by TBBPA exposure albeit not in dose-dependent manners. There were no effects of TBBPA on the expression of dio1 and dio2. We thus show that the two thyroid-hormone-disrupting chemicals PTU and TBBPA differ in their effect profiles with comparable effects on the studied phenotypes and thyroid-related gene expression to those reported in zebrafish.
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•PTU exposure reduced eye size, growth, and swim bladder inflation in Japanese medaka.•PTU exposure reduced swimming performance.•TBBPA exposure changed the expression of thyroid-related genes.•Molecular initiating event, key event, and adverse outcomes were identified.
In recent research, we found that the use of goggles and snorkel benefited non-swimmers with fear of water in a learn-to-swim program. Our purpose in this study was to examine the effects of using ...goggles and snorkel during a learn-to-swim program on the aquatic skills of young non-swimmers without fear of water. We modelled this research on our prior study. Following informed parental consent, 40 children (aged 10–11 years) were randomly divided into two groups: one that used goggles and snorkel (GS) and one that did not (NGS). After 4 weeks (five sessions per week) of learn-to-swim intervention, both groups improved aquatic skills such that the only group differences were for the blowing bubbles test, for which the learn-to-swim program resulted in smaller gains for the GS than the NGS group. Thus, the use (vs. non-use) of goggles and snorkels during the learn-to-swim program had no significant effect on most aquatic skills of young non-swimmers without fear of water. The only exception was a significant finding of reduced improvement in blowing bubbles in the goggles and snorkels group when compared to the no goggles and snorkel group. Together with past findings these results highlight important learn-to-swim differences between young non-swimmers with and without fear of water.
This study examined the swimming competence of primary school children, and how it was related to swimming activity, non-fatal aquatic events, and demographic factors. Primary school students ...(N = 4959; female = 2705, male = 2241; age range = 5 to 14 years) across 28 schools in the 15 districts of Hong Kong completed the Swimming Competence Questionnaire, and questions about their swimming experience, non-fatal aquatic events, and demographic variables. Descriptive statistics showed that over 60% of children could swim more than 5m, but less than 50% could swim over 25m. Over 50% of children were able to perform some basic swimming skills (e.g., holding breath underwater, floating, poolside/kickboard kicking, and treading water). Swimming competence was positively predicted by the demographic factors (i.e., age, sex, family income, and parents' highest education level), swimming experience, learning experience, and swimming location. Treading water was the only factor of swimming competence that established asignificant negative association with non-fatal aquatic events. Current results can be used to target key groups to improve children's swimming competence and reduce non-fatal aquatic events; children from lower socio-economic backgrounds and with less swimming experience should be encouraged to participate in more formal learn to swim lessons.
► PSC were extracted from the fins, scales, skins, bones and swim bladders of bighead carp. ► PSC from swim bladders and bones showed higher Tmax values than those from fins, scales and skins. ► PSC ...from the five tissues could all be used as a potential substitute for mammalian collagen.
The objective of this study was to extract and characterise pepsin-solubilised collagens (PSC) from the fins, scales, skins, bones and swim bladders of bighead carp and to provide a simultaneous comparison of five different sources from one species. The PSC were mainly characterised as type I collagen, containing two α-chains, and each maintained their triple helical structure well. The thermostability of PSC from the internal tissues (swim bladders and bones) was slightly higher than that of PSC from the external tissues (fins, scales and skins). The peptide hydrolysis patterns of all PSC digests using the V8 protease were similar. All PSC were soluble at acidic pH (1–6) and lost their solubility at NaCl concentrations above 30g/l. The resulting PSC from the five tissues would all be potentially useful commercially.
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