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Objective: This study aimed to explore the mechanism by which noise contributes to the development of Alzheimer's disease (AD)–like lesions. Method: Male Wistar rats (24 months) were allocated into two groups (n = 6 per groups): a noise group exposed to 98 dB sound pressure–level white noise for 4 hours daily from 8:00 to 12:00 for 30 days, and a control group without noise exposure. The cognitive functions of the rats were assessed using new-object recognition and Morris water maze tests. Then, hippocampal tissues were collected, and the levels of amyloid β 1-42 (Aβ1-42), Aβ1-40, brain-derived neurotrophic factor (BDNF), and tropomyosin receptor kinase B (TrkB) were measured using enzyme-linked immunosorbent assay (ELISA). Protein expression was evaluated through Western blot. Results: Noise exposure significantly impaired cognitive and recognition abilities, increased the escape latency, and decreased the number of crossings through the platform quadrant intersection and the time spent in the target quadrant (P < 0.01). The new-object exploration and recognition index of the rats in the noise group markedly decreased (P < 0.01). ELISA results indicated increases in Aβ1-40 and Aβ1-42 levels and decreases in BDNF and TrkB levels in the rat hippocampus in the noise group (P < 0.01). Western blot analyses revealed that beta-site amyloid precursor protein (APP) cleaving enzyme 1, phosphorylated tau protein, gamma-H2A histone family, member X, checkpoint kinase 2, p53, and p21 were remarkably elevated in the noise group (P < 0.01). Conclusion: Chronic noise exposure can cause hippocampal genetic damage in aged rats, leading to cognitive disorders and the development of lesions similar to those observed in AD. Thus, noise is a potential risk factor for neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Babylonia formosae habei is a commercially important marine gastropod species. Food particles ingested by the planktotrophic larvae of B. formosae habei can be critical in maximizing the larval growth and survival of this species. In this study, feeding rate responses of B. formosae habei larvae on cultured algae were observed using a Coulter multisizer. Variations were recorded based on the changes of different factors of influence, including varied larval stoking density, varied types of algae, varied algae concentrations and selective feeding on mixed algae cells of different types. Results of this study reveal some facts on the feeding of B. formosae habei larvae: larval stoking density has negative effect on their feeding rates; larva has a higher feeding rate on big-sized algae than small-sized algae; larva has a higher feeding rate on diatom than green algae and flagellate; feeding rate of larvae increased when fed mixed algae cells. Optimal algal concentration of the cultured algae Chlorella sp., Chaetoceros muelleri, Isochrysis zhanjiangensis and Dunaliella tertiolecta was suggested at 20 × 104, 5 × 104, 20 × 104 and 10 × 104 cells mL−1 respectively. Results of the preset study can be important in understanding feeding ecology of B. formosae habei larvae, and applicable for the aquaculture of this species. [ABSTRACT FROM AUTHOR]

Information of vertical distribution of longline-hook species is important for the development of effective measures to mitigate bycatch, and very helpful for better understanding of the oceanic ecosystem structure and implementation of ecosystem-based fisheries management. Based on depth data of longline hook and capture hook position of pelagic species, collected by on board scientific observer in the southeast Pacific Ocean from September 2013 to January 2014, shoaling rate of longline hook and vertical distribution of 14 pelagic species were analyzed. The results showed that the relative shoaling rate range of longline hook was 8.9%-17.1%, and the average relative shoaling rate was 13.5%. The depth ranges of 14 capture species were different. The species with the deepest depth was Opah (Lampris guttatus) , and the species with the shallowest depth was skipjack (Katsuwonus pelamis). Except for yellowfin tuna (Thunnus albacares) and striped marlin (Tetrapturus audax) , the mean depth and depth distributions of bycatch species were significantly different from that of the targeted albacore tuna (Thunnus alalunga). [ABSTRACT FROM AUTHOR]

Coilia nasustaihuensis is the most abundant species in Dianshan Lake and plays an important role in the lake ecosystem. From July 2010 to August 2011, a total of 3107 samples of C. nasustaihuensis were collected from Dianshan Lake. Based on length data of these samples, ELEFAN I technique was employed to estimate growth and mortality parameters, and the Beverton-Holt dynamic model was used to evaluate the population dynamics trend for C. nasustaihuensis. Growth of this species was described using a von Bertalanffy model, and the estimated parameters were L∞=35. 70 cm, k =0. 54, and t0 =-0. 48 a. The turning point for body mass growth curve of the stock was situated at t =1. 37 a. Natural mortality coefficient M was then estimated using Pauly's empirical equation and found to be 0. 872. Length-converted catch curves were used to estimate the total mortality coefficient Z, which was found to be 2. 121. Accordingly, the fishing mortality coefficient (F) was equal to 1. 249, and the current exploitation rate was 0. 589, suggesting the stock was over-exploited. According to the Beverton-Holt dynamic model, the minimum capture size for C. nasustaihuensis should be 21. 42 cm (age 1. 22 years). [ABSTRACT FROM AUTHOR]

Objective: Naringin is a flavonoid derived from Chinese herbs. According to earlier studies, naringin may have the potential to alleviate aging-induced cognitive dysfunction. Therefore, this study attempted to explore the protective effect and underlying mechanism of naringin on aging rats with cognitive dysfunction., Methods: After the construction of a model of aging rats with cognitive dysfunction through subcutaneous injection of D-galactose (D-gal; 150 mg/kg), intragastric administration of naringin (100 mg/kg) was performed for treatment. Behavioral tests, including Morris water maze test (MWM), novel object recognition test (NORT), and fear conditioning test, were used to measure the cognitive function; ELISA and biochemical tests were used to determine the levels of interleukin (IL)-1 β , IL-6, monocyte chemoattractant protein-1 (MCP-1), brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) in the hippocampus of rats in each group, respectively; H&E staining was used to observe the pathological changes in the hippocampus; Western blot was used to examine the expression of toll-like receptor 4 (TLR4)/NF- κ B pathway-related proteins and endoplasmic reticulum (ER) stress-related proteins in the hippocampus., Results: The model was successfully constructed by subcutaneous injection of D-gal (150 mg/kg). The behavioral test results showed that naringin could ameliorate the cognitive dysfunction and alleviate the histopathological damage of hippocampus. Moreover, naringin significantly improve the inflammatory response (the levels of IL-1 β , IL-6, and MCP-1 were decreased), oxidative stress response (MDA level was increased while GSH-Px activity was decreased), and ER stress (the expression of glucose-regulated protein 78 (GRP78), C/-EBP homologous protein (CHOP), and transcription factor 6 (ATF6) expression was downregulated), and increased the levels of neurotrophic factors BDNF and NGF in D-gal rats. Besides, further mechanistic studies revealed the downregulation of naringin on TLR4/NF- κ B pathway activity., Conclusion: Naringin may inhibit inflammatory response, oxidative stress, and ER stress by downregulating TLR4/NF- κ B pathway activity, thereby improving cognitive dysfunction and alleviating histopathological damage of hippocampus in aging rats. Briefly, naringin is an effective drug for the treatment of cognitive dysfunction., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2023 Xiao-jie Dai et al.)

Stable carbon and nitrogen isotope ratios (δ 13 C and δ 15 N, respectively) of multiple tissues with different turnover rates can provide trophic information at different timescales, and thus play an important role in tracing the changes of feeding, habitat utilization and trophic niche of consumers. The δ 13 C and δ 15 N contents of muscle, liver and blood of blue sharks ( Prionace glauca ), longfin mako sharks ( Isurus paucus ), crocodile sharks ( Pseudocarcharias kamoharai ) and shortfin mako sharks ( I. oxyrinchus ) from tropical Atlantic were measured, and the trophic niche was evalua-ted. The results showed that I. oxyrinchus , P. kamoharai , and P. glauca had similar δ 15 N values, higher than that of I. paucus . Feeding segregation was found between P. glauca and other species, showing unique trophic niche. The largest trophic niche width was observed in I. oxyrinchus , indicating the high diversity of prey and (or) feeding habitats. High trophic niche overlap was found in P. kamoharai and I. oxyrinchus , implying their potential competition for resources. There was no correlation between the differences among tissues in the δ 13 C or δ 15 N values and the body size of I. oxyrinchus , P. kamoharai and P. glauca , indicating no recent diet shifts for those species. I. paucus showed significant correlation between δ 15 N differences in liver, blood and muscle with the shark fork length, indicating its short-term diet shift. The similarity of δ 13 C and δ 15 N values and the higher metabolic rates of liver and blood were found in all four shark species, implying the similar incorporation rates of both tissues, which were considered as the short-term indicator of diet.

Yangtze River Estuary is the biggest estuarine ecosystem in the western Pacific Ocean. Evaluating fish community in this ecosystem can provide scientific basis for its restoration and mana-gement. Generalized additive model (GAM) and boosted regression tree (BRT) were built to examine the relationship between fish community diversity and environmental and spatio-temporal variables based on data collected during 2012-2014. Combined with linear regression analysis, a cross validation was used to evaluate the fitness and predictive performance of both models. We plotted the spatial distribution of fish community diversity and richness in each station of the Yangtze River Estuary in 2014. The results showed that salinity, pH and chlorophyll-a had the most contribution on diversity, while pH, dissolved oxygen and chlorophyll-a were the most contributive variables on richness. BRT models showed better fitness and lower prediction error than GAM models. In contrast to GAM models, BRT models could distinguish the fish community index in each station area with respect to the spatial prediction. The diversity index in external water was obviously greater than that in internal water. Meanwhile, the station at higher latitude had a higher diversity index in both external and internal water.

Crocodile shark (Pseudocarcharias kamoharai) is an important by-catch species of tropical Atlantic tuna longline fishery. The research on the relationship between the CPUE (catch per unit effort) and environmental factors can provide basic data for resource protection and management of this important species. Based on the Tweedie distribution theory, and the data of 1085 croco-dile sharks collected by the national observers of longline fishery from 2009 to 2015 in the tropical Atlantic Ocean (6.38° S-14.92° N, 42.03°-18.53° W), theGAM-Tweedie model was established, and the temporal and spatial effects of CPUE as well as the relationship with environmental factors were analyzed. The results showed the explained cumulative deviance of the crocodile shark's CPUE to be 40.2%. The spatio-temporal factors (year, month, longitude, latitude) all hadsignificant effects (P<0.05) on the crocodile shark CPUE. The environmental factors such as sea surface height, chlorophyll a concentration, weather code, sea surface salinity and sea level pressure all had significant effects on CPUE (P<0.05). However, the Beaufort wind force and lunar calendar did not have significant effects on theCPUE (P>0.05). Significant correlation (P<0.05) was observed at different latitudes and in months between the sea surface temperature and CPUE. The standardized CPUE of the crocodile shark in 2009-2015 showed a fluctuating increase trend.

Sample size plays a significant role in determining accuracy and precision for estimates of fish population dynamics or fish communities. A fisheries survey that estimated the fish community in Dianshan Lake was conducted as a case study to determine the necessary sample size for such estimates. Monthly surveys of 24 survey stations in Dianshan Lake were conducted from July, 2010 to June, 2011, resulting in the collection of 45 fish species from 14 families. A resampling technique was used to estimate the optimal survey times and number of survey stations for a Dianshan Lake fishery survey. Results showed a negative relationship between the number of stations per survey and survey times per year. To maintain a 90% fixed percentage of fish species detection and 95% fixed probability of detection within the fishery survey, the required sample sizes were 19 and 21 stations per survey and 12 and 11 survey times per year, correspondingly. The Shannon diversity index increased with the number of stations before reaching equilibrium, therefore, the optimal survey stations for estimating fish biodiversity of the Dianshan Lake fishery was determined to be 21 stations. This study provided a framework for determining the optimal sampling effort in similar studies at other locations.

The blue shark, Prionace glauca, is the main by-catch species in tuna longline fishery. As one of top species in the oceanic food webs, the blue shark plays an important role in the marine ecosystem. Traditional stock assessment methods are difficult to accurately evaluate the population dynamic for this shark because of limited data. Based on life-history parameters of the blue shark in the North Atlantic, demographic analysis was employed to estimate the demographic parameters and evaluate the potential exploitation for the blue shark. Moreover, we discussed the relationship between age at first capture and critical value of fishing mortality corresponding to the value of intrinsic rate of natural increase 0. The results showed that the survival rate (S) of blue shark from 0.719 to 0.820, intrinsic rate of natural increase (r0) from 0.250 to 0.381, time of population doubling (tx2) from 1.819 to 2.773 years, reproduction rate per generation (R0) from 6.600 to 22.255, and generation time (G) from 8.498 to 10.162 years. The sensitivity analysis for the life history parameters revealed that the uncertainties of natural mortality existed in the first age class, age at maturity and maximum age had slight influence on the demographic parameters. Fishing mortality (Fc) increased with the age at first capture. When the age at first capture (tc) was more than five, there was no obvious relationship between Fc and tc.

Information of vertical distribution of longline-hook species is important for the development of effective measures to mitigate bycatch, and very helpful for better understanding of the oceanic ecosystem structure and implementation of ecosystem-based fisheries management. Based on depth data of longline hook and capture hook position of pelagic species, collected by on board scientific observer in the southeast Pacific Ocean from September 2013 to January 2014, shoaling rate of longline hook and vertical distribution of 14 pelagic species were analyzed. The results showed that the relative shoaling rate range of longline hook was 8.9% - 17.1%, and the average relative shoaling rate was 13.5%. The depth ranges of 14 capture species were different. The species with the deepest depth was Opah (Lampris guttatus), and the species with the shallowest depth was skipjack (Katsuwonus pelamis). Except for yellowfin tuna (Thunnus albacares) and striped marlin (Tetrapturus audax), the mean depth and depth distributions of bycatch species were significantly different from that of the targeted albacore tuna (Thunnus alalunga).

Coilia nasustaihuensis is the most abundant species in Dianshan Lake and plays an important role in the lake ecosystem. From July 2010 to August 2011, a total of 3107 samples of C. nasustaihuensis were collected from Dianshan Lake. Based on length data of these samples, ELEFAN I technique was employed to estimate growth and mortality parameters, and the Beverton-Holt dynamic model was used to evaluate the population dynamics trend for C. nasustaihuensis. Growth of this species was described using avon Bertalanffy model, and the estimated parameters were Linfinity = 35.70 cm, k = 0.54, and t0 = -0.48 a. The turning point for body mass growth curve of the stock was situated at t = 1.37 a. Natural mortality coefficient M was then estimated using Pauly's empirical equation and found to be 0. 872. Length-converted catch curves were used to estimate the total mortality coefficient Z, which was found to be 2.121. Accordingly, the fishing mortality coefficient (F) was equal to 1.249, and the current exploitation rate was 0. 589, suggesting the stock was over-exploited. According to the Beverton-Holt dynamic model, the minimum capture size for C. nasustaihuensis should be 21.42 cm (age 1.22 years).