De novo metabolic syndrome after liver transplantation: a meta-analysis on cumulative incidence, risk factors, and outcomes.

Post-transplant metabolic syndrome (PTMS) has been associated with increased cardiovascular risk which significantly impacts the morbidity and mortality rates of liver transplant (LT) recipients. This study sought to conduct a meta-analysis and systematic review on the cumulative incidence, risk factors, and cardiovascular outcomes associated with de novo PTMS.Medline and Embase were searched for articles describing the incidence, risk factors, and cardiovascular outcomes of de novo PTMS. Meta-analysis of proportions was conducted to calculate incidence. Conventional pairwise analysis using random effects model was used to tabulate OR and hazard ratio for risk factors and cardiovascular outcomes, respectively. Fifteen studies involving 2683 LT recipients were included. Overall rate of de novo PTMS was 24.7% (CI: 18.0%-32.9%) over a mean follow-up period of 15.3 months and was highest in patients with NAFLD (60.0%, CI: 52.0%-67.5%) compared with other liver diseases. Older age (OR: 1.05, CI: 1.01-1.09, p = 0.02) and pre-LT type II diabetes mellitus (OR: 5.00, CI: 4.17-5.99, p < 0.01) were predictive factors of de novo PTMS. Patients with de novo PTMS had significantly higher likelihood of cardiovascular disease events compared with those who did not (hazard ratio: 2.42, CI: 1.54-3.81, p < 0.01). De novo PTMS is a common complication and is significantly associated with increased cardiovascular disease morbidity. High-risk patients such as elderly recipients, those with pre-LT type II diabetes mellitus, or NASH-related cirrhosis should undergo routine screening to allow timely intervention.

Quality Assessment of Ultrasound and Magnetic Resonance Imaging for Hepatocellular Carcinoma Surveillance: A Systematic Review and Meta-Analysis.

INTRODUCTION: To achieve early detection and curative treatment options, surveillance imaging for hepatocellular carcinoma (HCC) must remain of quality and without substantial limitations in liver visualization. However, the prevalence of limited liver visualization during HCC surveillance imaging has not been systematically assessed. Utilizing a systematic review and meta-analytic approach, we aimed to determine the prevalence of limited liver visualization during HCC surveillance imaging. METHODS: MEDLINE and Embase electronic databases were searched to identify published data on liver visualization limitations of HCC surveillance imaging. An analysis of proportions was pooled using a generalized linear mixed model with Clopper-Pearson intervals. Risk factors were analysed using a generalized mixed model with a logit link and inverse variance weightage. RESULTS: Of 683 records, 10 studies (7,131 patients) met inclusion criteria. Seven studies provided data on liver visualization limitations on ultrasound (US) surveillance exams: prevalence of limited liver visualization was 48.9% (95% CI: 23.5-74.9%) in the overall analysis and 59.2% (95% CI: 24.2-86.9%) in a sensitivity analysis for cirrhotic patients. Meta-regression determined that non-alcoholic fatty liver disease was associated with limited liver visualization on US. Four studies provided data for liver visualization limitations in abbreviated magnetic resonance imaging (aMRI), with inadequate visualization ranging from 5.8% to 19.0%. One study provided data for complete MRI and none for computed tomography. CONCLUSION: A substantial proportion of US exams performed for HCC surveillance provide limited liver visualization, especially in cirrhosis, which may hinder detection of small observations. Alternative surveillance strategies including aMRI may be appropriate for patients with limited US visualization.

High-performance liquid chromatographic determination of multi-mycotoxin in cereals and bean foodstuffs using interference-removal solid-phase extraction combined with optimized dispersive liquid-liquid microextraction.

A novel pre-treatment was proposed for the simultaneous determination of aflatoxins, ochratoxin A and zearalenone in foodstuffs using high-performance liquid chromatography with fluorescence detection. The analytical procedure was based on a first step using a quick, easy, cheap, effective, rugged, and safe based extraction procedure, followed by salting out and purification with a C18 solid-phase extraction column as interference removal clean-up. Subsequently, collected supernatant was subjected to dispersive liquid-liquid microextraction. Response surface methodology based on central composite design was employed to optimize conditions in the microextraction procedure. Under the optimum conditions, satisfactory analytical performance with recoveries ranging from 63.22 to 107.6% were achieved in different types of cereals and beans, as well as desirable precisions (0.81-8.13%). Limits of detections and quantifications for these six mycotoxins ranging from 0.03 to 13 µg/kg and 0.22 to 44 µg/kg, respectively, were obtained. Finally, the established method was successfully validated by four certified reference materials (P = 0.897 > 0.05) and applied to 79 samples from local markets.

Simultaneous and rapid determination of deoxynivalenol and its acetylate derivatives in wheat flour and rice by ultra high performance liquid chromatography with photo diode array detection.

A simple and reliable method of ultra high performance liquid chromatography coupled with photo-diode array detection has been proposed for the simultaneous determination of deoxynivalenol and its acetylated derivatives in wheat flour and rice, especially focusing on the optimization of sample extraction, cleanup, and chromatographic separation conditions. Sample pretreatment consisted of a first step using a quick, easy, cheap, effective, rugged, and safe based extraction procedure and a subsequent cleanup step based on solid-phase extraction. The method was extensively validated in wheat flour and rice, obtaining satisfactory analytical performance with good linearity (R(2) ≥ 0.999), acceptable recoveries (80.0-104.4%), and repeatability (RSDs 1.3-10.7%). The limits of detection (21.7-57.4 µg/kg) and quantitation (72.3-191.4 µg/kg) for deoxynivalenols were lower than those usually permitted by various countries' legislation in these food matrices. The method was applied to 34 wheat and rice samples. The results were further compared with results of ultra high performance liquid chromatography with electrospray ionization tandem mass spectrometry.

Study of the matrix effects of tetrodotoxin and its content in cooked seafood by liquid chromatography with triple quadrupole mass spectrometry.

Tetrodotoxin is a marine biotoxin with high acute toxicity. The levels in cooked seafood will help us to assess its intake in humans and may help assess the risk of toxicity. However, heavy matrices hinder the direct quantitation of tetrodotoxin. A quantitative method of measuring tetrodotoxin in cooked seafood using liquid chromatography with triple quadrupole mass spectrometry was established in this study. Tetrodotoxin was extracted from the sample matrix using 2% formic acid in methanol and cleaned using a cation exchange cartridge. The cleanup conditions were optimized. The matrix effects were determined using the postextraction spiking method and by comparing the slope of the linear regression equation in sample matrix to that in solvent. The limit of detection in the sample matrix was 5 µg/kg and the limit of quantification was 10 µg/kg. The mean recoveries at three spiking levels were 66.9-89.2% with relative standard deviations of 5.0-10.8% (n = 6) in five different matrices. Tetrodotoxin was found at concentrations of 26.1-2462 µg/kg in nine of 83 cooked seafoods tested in this study. Eight analogs of Tetrodotoxin were detected in the samples studied.

Application of UPLC-MS/MS Method for Analyzing B-vitamins in Human Milk.

OBJECTIVE: To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). METHODS: The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column (2.1×100 mm, 1.8 µm). The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESI+ionization and detected in multiple reaction monitoring (MRM) with three acquisition functions. RESULTS: Calibration curves ranged from 0.5-160 ng/mL (thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal), and 2.5-800 ng/mL (pantothenic acid, FAD and nicotinamide) (R2=0.990-0.999). The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification (LOQ) for all vitamins was between 0.25 and 3 µg/L. CONCLUSION: This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.

[Feeding ecology of Chaeturichthys stigmatias during autumn in Haizhou Bay]. / 海州湾秋季矛尾虾虎鱼的摄食生态.

Research about feeding ecology of fish is important to understand individual behavior and population development, which is also the basic to analyze trophic structure and function of aquatic ecosystems. Chaetrichthys stigmatias is one of the key species in the Haizhou Bay fisheries ecosystem, which has critical ecological niche within the food web. In this study, we collected samples through bottom trawl surveys during the fall of 2018 in the Haizhou Bay, and analyzed the feeding ecology of C. stigmatias based on both stomach content analysis and stable isotope technology. The results showed that the primary diet groups for C. stigmatias were Ophiuroidea and Shrimp, including Ophiothrix marenzelleri, Ophiopholis mirabilis, Ophiura sarsii, Penaeidae, and Alpheus japonicus. The range of δ13C values of C. stigmatias was from -19.39‰ to -15.74‰, with an average value of (-18.07±0.87)‰, which had no significant correlation with body length. The range of δ15N values was from 8.16‰ to 12.86‰, with an average value of (10.14±1.51)‰, which was positively correlated with body length. The trophic level of C. stigmatias showed a positive relationship with body length, with an average value of (3.74±0.34) and a range value of 3.32 to 4.20 among different size groups. The contribution rates of different prey groups varied significantly. Based on the structural equation modeling, we found that the feeding intensity of C. stigmatias was primally influenced by body length, sea bottom salinity, sea bottom temperature, and water depth, with a particularly signi-ficant positive correlation with body length. The combination of stable isotope technology and stomach content analysis methods could contribute to comprehensive understanding on the feeding ecology of C. stigmatias, providing essential data and foundation for research on trophic structures and resource conservation in the Haizhou Bay ecosystem.

Dry Ball-Milled Quinoa Starch as a Pickering Emulsifier: Preparation, Microstructures, Hydrophobic Properties and Emulsifying Properties.

This research supplied a "cleaner-production" way to produce "clean-label" quinoa starch-based Pickering emulsifier with excellent emulsifying properties. The effects of dry ball-milling time and speed on the multi-scale structures and emulsifying properties of quinoa starch were studied. With increasing ball-milling time and speed, particle size first decreased and then increased, the crystallinity, lamellar structure and short-range ordered structure gradually decreased, and contact angle gradually increased. The increased contact angle might be related to the increased oil absorption properties and the decreased water content. The emulsification properties of ball-milled quinoa starch (BMQS)-based Pickering emulsions increased with the increase in ball-milling time and speed, and the emulsions of BMQS-4 h, 6 h, 8 h, and 600 r reached the full emulsification state. After 120 days' storage, the oil droplets of BMQS-2 h (BMQS-400 r) deformed, the oil droplets increased, and the emulsification index decreased. The emulsification index and the oil droplets of BMQS-4 h, 6 h, 8 h and 600 r-based emulsions did not show obvious changes after storage, indicating the good emulsifying stability of these BMQS-based emulsions, which might be because that the relatively larger amount of starch particles that dispersed in the voids among the oil droplets could act as stronger network skeletons for the emulsion gel. This Pickering emulsifier was easily and highly efficiently produced and low-cost, having great potential to be used in the food, cosmetic and pharmaceutical industries.

Species composition and spatial and temporal distribution of occasional fishes in Haizhou Bay, Shandong, China.

Occasional species are often neglected in community ecology studies due to low abundance and frequence. However, they are closely related to biodiversity maintenance and marine conservation. We used index of relative importance (IRI), distribution center of gravity and Mann-Kendall trend test to elucidate the spatial and temporal distributions and changing trends of occasional fishes in Haizhou Bay based on the fishery resources survey data collected from 2013 to 2019. The occasional fishes in Haizhou Bay was identified based on IRI. Nine of the occasional species were selected to analyze the spatial distribution and interannual trends of relative biomass and occurrence frequency. The results showed that a total of 93 fish species were recorded in the multi-year survey in Haizhou Bay. Among which, 61 species had IRI<10, indicating the existence of a large number of occasional fishes in Haizhou Bay. The nine selected occasional species had distinctive spatial distribution characteristics. Erisphex pottii, Azuma emmnion, and Raja porosa were mainly distributed in the eastern part of Haizhou Bay, with a wide habitat range. Sphyraena pinguis, Coilia nasus, and Zebrias zebra were distributed in the western and southern parts, respectively. The rest species were mainly distributed in the southwestern part. In terms of interannual variation, the biomass and occurrence frequency of Coilia mystus, R. porosa, A. emmnion, and S. pinguis showed fluctuating changes, while Odontamblyopus rubicundus and Ctenotrypauchen microcephalus showed an increasing trend. The biomass and occurrence of Z. zebra, C. nasus and E. pottii gradually decreased with no catch in recent years. This study would contribute to the understanding of the spatial and temporal distribution of occasional species, and provide guidance for the conservation of occasional biological resources and species diversity, especially for the establishment of marine protected areas.

Influencing factors of predation on five keystone prey species in Haizhou Bay based on Delta-GAMMs.

Trophic dynamics is one of the major regulators of fishery production in marine ecosystems, which is important for the implementation of ecosystem-based fisheries management. Based on data collected form bottom trawl surveys in Haizhou Bay and adjacent waters during autumn of 2011 and 2018, Delta-GAMMs (Delta-generalized additive mixed models) were constructed to evaluate the effects of biotic and abiotic factors on the predation of five key prey species (including Leptochela gracilis, Alpheus japonicus, Loligo spp., Larimichthys polyactis, and Oratosquilla oratoria) in the Haizhou Bay. Percent frequency of occurrence and predation pressure index were used to identify their major predators. Variance inflation factor and full subsets regression were analyzed to quantify the degree of multicollinearity between these factors. The results showed that the occurrence frequency of keystone prey species in the stomach of predators ranged from 8.5% to 42.2%, and the weight percentage ranged from 4.2% to 40.9%. The average deviance explanation rate of the "binomial" model was 16.1%, and the average deviance explanation rate of the "positive" model was 23.8%. Body length of predator, predator population density, and sea bottom temperature were important factors influencing prey-predator trophic interactions. Predator length was the most important factor, with feeding probability and weight percentage of keystone prey species all increasing with body length of predator. Feeding probability and weight percentage of key prey species decreased with predator population density. The effects of environmental factors such as sea bottom temperature, depth of water, latitude, and sea bottom salinity showed different trends, depending on the prey-predator assemblage. This study showed that the Delta-GAMMs was an effective method to explore the trophic interactions between prey and predators in marine ecosystems, and could provide a theoretical basis for the conservation and sustainable use of fisheries resources.

[Habitat characteristics of Octopus ocellatus and their relationship with environmental factors during spring in Haizhou Bay, China]. / æµ·å·žæ¹¾æ˜¥å­£çŸ­è›¸çš„æ –æ¯åˆ†å¸ƒç‰¹å¾åŠå ¶ä¸ŽçŽ¯å¢ƒå› å­çš„å ³ç³».

In recent years, a variety of important fishery resources in China's coastal waters have declined. Octopus ocellatus has the characteristics of short life cycle and rapid growth, with great contributions to fisheries of China's coastal waters. However, we know little about the habitat distribution characteristics of O. ocellatus and its relationship with environmental factors, which is not conducive to better protection and utilization of its resources. Here, we analyzed the distribution characteristics of O. ocellatus and its relationship with environmental factors using three machine learning methods, i.e., random forest model, artificial neural network model, and generalized boosted regression models, based on the survey data of fishery resources and habitat in Haizhou Bay during spring of 2011 and 2013-2017. Among the three models, random forest model had great advantages in the fitting effect and prediction ability. The model analysis results showed that sea bottom temperature, seawater depth and sea bottom salinity had significant effects on the habitat distribution of O. ocellatus. The relative resource density of O. octopus increased first and then decreased with the increases of sea bottom temperature, seawater depth, and sea bottom salinity. Based on environmental data simulated by the FVCOM model, we predicted the habitat distribution of O. ocellatus in Haizhou Bay using random forest model and found that O. ocellatus was mainly distributed in the area between 34.5°-35.8° N and 119.7°-121° E.

[Spatio-temporal variations in species composition and diversity of fish communities in the adjacent waters of Changshan Islands, China]. / é•¿å±±åˆ—å²›é‚»è¿‘æµ·åŸŸé±¼ç±»ç¾¤è½ç§ç±»ç»„æˆå’Œå¤šæ ·æ€§æ—¶ç©ºå˜åŒ–.

In order to understand species composition and diversity of fish communities in the ecotone between the Yellow Sea and Bohai Sea, we examined species composition and temporal and spatial variations of fish species diversity using the relative importance index (IRI), species diversity index and k dominance curve based on bottom trawl survey data of fish resources in the adjacent waters of the Changshan Islands in October 2016, January, May and August 2017. The results showed that 77 fish species were captured, mainly temperate water fishes, demersal fishes and migratory fishes. The dominant species exhibited obvious seasonal variation. The dominant species in spring and winter were Lophius litulon, and those in summer were pelagic species such as Scomber japonicus and Engraulis japonicus. A total of 46 migratory fish species were found throughout the year. The seasonal species migration indices were all higher than 100, while the species migration index was the largest in autumn. The species diversity index showed high spatial and temporal dynamics, with the highest species richness in spring and the highest Shannon diversity and evenness in autumn. There was a significant negative correlation between species richness and sea surface temperature in summer, significant positive correlations between species richness and depth and bottom temperature in winter, and a significant positive correlation between Shannon diversity index and sea bottom temperature. In short, fish community showed high species diversity, rich migratory species and obvious temporal and spatial heterogeneity in the adjacent waters of the Changshan Islands, which is an ecotone between the Yellow Sea and the Bohai Sea.

[Feeding ecology of Amblychaeturichthys hexanema in Haizhou Bay based on linear mixed model]. / åŸºäºŽçº¿æ€§æ··åˆæ¨¡åž‹ç ”ç©¶æµ·å·žæ¹¾å ­ä¸é’å°¾è™¾è™Žé±¼æ‘„é£Ÿç”Ÿæ€.

Many traditional economic marine fishery resources have been declining in the coastal waters of China. Amblychaeturichthys hexanema has become one of the dominant species in Haizhou Bay and some other coastal areas of China, playing an important role in marine food webs. We analyzed the feeding strategy of A. hexanema based on the bottom trawl surveys conducted in the Haizhou Bay and adjacent waters in spring and autumn of 2011 and 2013-2016. The feeding habits and main influencing factors of A. hexanema were studied using linear mixed model (LMM). The results showed that A. hexanema fed on 14 prey groups, with Amphipoda, shrimps, Bivalvia and Ophiuroidea as the main prey groups. A total of 37 species were identified in the preys. The dominant prey species were Gammarus sp., Leptochela gracilis, Monoculodes sp., Moerella iridescens and Alpheus distinguendus. Results of the linear mixed model showed that the feeding intensity of A. hexanema in Haizhou Bay was influenced by body length, water depth, survey season, and bottom water salinity. Among them, water depth and bottom salinity had significantly negative effects, whereas the impact of body length was significantly positive. The feeding intensity was significantly higher in spring than that in autumn. Results of cluster analysis showed that A. hexanema had different feeding habits between two length groups as divided by a threshold of 70 mm body length. The change of feeding habit was mainly attributed to the variations in predation ability and food availability. Feeding strategy analysis showed that trophic niche of A. hexanema had large components between phenotypes and low intraspecific competition for prey. This study would contribute to our understanding of life history characteristics and ecological habits of A. hexanema, and provide scientific support for the sustainable utilization and management.

Factors early in life associated with hepatic steatosis.

BACKGROUND: The rise in prevalence of non-alcoholic fatty liver disease (NAFLD) mirrors the obesity epidemic. NAFLD is insidious but may gradually progress from simple steatosis to steatohepatitis, fibrosis and cirrhosis and/or hepatocellular carcinoma. Intervention strategies to ameliorate developmental programming of NAFLD may be more efficacious during critical windows of developmental plasticity. AIM: To review the early developmental factors associated with NAFLD. METHODS: Databases MEDLINE via PubMed, and EMBASE and Reference Citation Analysis were searched and relevant publications up to April 30, 2021 were assessed. Original research studies that included risk factors associated with early development of NAFLD in human subjects were included. These factors include: Maternal factors, intrauterine and prenatal factors, post-natal factors, genetic and ethnic predisposition, childhood and adolescence environmental factors. Studies were excluded if they were review articles or animal studies, case reports or conference abstracts, or if NAFLD was not clearly defined and assessed radiologically. RESULTS: Of 1530 citations identified by electronic search, 420 duplicates were removed. Of the 1110 citations screened from title and abstract, 80 articles were included in the final analysis. Genetic polymorphisms such as patatin-like phospholipase domain-containing protein 3 (PNPLA3) and membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) were associated with increased risk of NAFLD. Familial factors such as maternal obesogenic environment and parental history of hepatic steatosis was associated with offspring NAFLD. Longer duration of exclusive breastfeeding in infancy was associated with a lower risk of developing NAFLD later in life while metabolic dysfunction and/or obesity in adolescence was associated with increased risk of NAFLD. Studies relating to socioeconomic factors and its association with NAFLD reported confounding results. CONCLUSION: Maternal metabolic dysfunction during pregnancy, being exclusively breastfed for a longer time postnatally, diet and physical activity in childhood and adolescence are potential areas of intervention to decrease risk of NAFLD.

Historical Changes in Weight Classes and the Influence of NAFLD Prevalence: A Population Analysis of 34,486 Individuals.

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally in tandem with the growing obesity epidemic. However, there is a lack of data on the relationship between historical weight changes 10 years ago and at present on NAFLD prevalence at the population level. Therefore, we sought to evaluate the relationship between weight classes and the prevalence of NAFLD. Methods: Data were used from the United States National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Univariate and multivariate general linear model analyses were used to obtain risk ratio (RR) estimations of NAFLD events. Results: In total, 34,486 individuals were analysed, with those who were lean at both time points as the control group. Overweight (RR: 14.73, 95%CI: 11.94 to 18.18, p < 0.01) or obese (RR: 31.51, 95%CI: 25.30 to 39.25, p < 0.01) individuals at both timepoints were more likely to develop NAFLD. Residual risk exists where previously obese individuals became overweight (RR: 14.72, 95%CI: 12.36 to 17.52, p < 0.01) or lean (RR: 2.46, 95%CI: 1.40 to 4.31, p = 0.02), and previously overweight individuals who became lean (RR 2.24, 95%CI 1.42 to 3.54, p = 0.01) had persistent elevated risk of developing NAFLD despite weight regression. Sensitivity analysis identified that a higher proportion of individuals with regression in weight class were diabetics and Mexican Americans, while fewer African Americans saw weight-class regression. Conclusions: Residual risk exists in patients who lost weight despite the smaller magnitude of effect, and targeted weight reductions should still be used to mitigate the risk of NAFLD at the population level.

Multi-residue analysis of pesticides in tea by online SEC-GC/MS.

A multi-residue method for the analysis of pesticides in tea was developed by online size exclusion chromatography (SEC)-GC/MS with full scan mode. The sample was fortified with chlorpyrifos-d(10) isotope internal standard and extracted by acetonitrile. After purification by primary secondary amine sorbent and solvent exchange by SEC mobile phase, the sample was detected by online SEC-GC/MS. The purification result of the online system was evaluated by comparing the correlation between Chinese cabbage and tea matrix. The factors for method optimization included sample preparation, matrix effects and the instrument parameters of each online component. Scatter plot was introduced in this study to directly illustrate the results of the condition optimization and matrix effects in the online system. For most of the pesticides, the average recoveries ranged from 70 to 130% and the RSD were below 15%. The feasibility of the application of full scan mode in multi-residue determination of trace amounts of pesticides (LODs below 0.01 mg/kg) in a complex matrix was discussed.

Understanding the feeding ecology of Cynoglossus joyneri in Haizhou Bay based on stable isotope analysis.

We analyzed the feeding ecology of Cynoglossus joyneri by carbon and nitrogen stable isotope analysis based on the samples collected from the bottom trawl surveys during spring and autumn of 2018 in Haizhou Bay, China. The results showed that the δ13C and δ15N values of C. joyneri ranged from -20.75‰ to -15.91‰ and from 5.98‰ to 12.02‰, respectively. The mean values of the δ13C and δ15N were (-17.79±1.00)‰ and (9.37±1.33)‰, respectively. There was a significantly negative correlation between the δ13C values and standard length and a positive correlation between the δ15N values and standard length. The mean trophic level of C. joyneri was (3.43±0.97). There was a significantly positive correlation between the trophic level and standard length. The dominant prey groups of C. joyneri were fish, crabs, shrimps, mollusca, polychaeta, plankton and particle organic matter (POM). The trophic contribution of shrimps was the highest among these prey groups. The trophic contribution of fish, crabs and shrimps was higher in autumn than those in spring. This study would help to understand the role of C. joyneri in the material cycling and energy flow in Haizhou Bay ecosystem, and provide scientific basis for the protection and rational utilization of this species.

[Sampling design optimization based on estimation accuracy and survey cost for fishery-independent surveys]. / åŸºäºŽä¼°è®¡å‡†åº¦å’Œè°ƒæŸ¥è´¹ç”¨çš„æ¸”ä¸šèµ„æºè°ƒæŸ¥é‡‡æ ·è®¾è®¡ä¼˜åŒ–.

Optimization of sampling design can reduce survey cost, ensure the accuracy of survey data, and get the maximum benefit of survey design. In this study, survey voyage was added into sampling survey design optimization as the evaluation index to quantify the survey cost. Computer simulation and resampling technique were used to simulate the survey plan. Simulation annealing algorithm was used to find the survey design with the shortest voyage. Based on the survey data collected from the bottom trawl survey conducted in the Haizhou Bay and its adjacent waters in spring and autumn from 2013 to 2015, Kriging interpolation was used to simulate the relative abundance distribution of Conger myriaster, Enedrias fangi, and Hexagrammos otakii in the bay in two seasons as their 'true' values. Resampling was conducted using stratified random sampling with different sample sizes for simulation study, and the abundance indices of each target species were estimated based on the simulated data. The relative bias (RB) was used to evaluate the accuracy of estimation of abundance index. The average survey cost and probability of budget overshoot (P) were used to measure the cost of survey. Integrated evaluation index (IEI) was developed to measure the survey cost and estimation accuracy comprehensively. The results showed RB values of all target species decreased with sample size. Different target species had different RB values with the same sample size. The optimal numbers of station determined by different evaluation indices were different. The optimal sample size determined by RB was relatively high, while the cost exceeded the budget of survey. The optimal sample size determined by probability of exceeding survey budget was relatively low but the accuracy and precision of estimation was low. IEI balanced the survey cost and estimation accuracy, and the optimal sample size defined by IEI was at intermediate level. The sampling design considering survey cost and route planning could not only determine the optimal sample size, but also record the potential station location, the survey sequence and the corresponding survey cost of simulations. According to the actual cost budget, the desired survey design with low cost and low RB of estimation from simulations could be chosen for fishery-independent surveys.

Development of the fingerprint for the quality of Radix Linderae through ultra-pressure liquid chromatography-photodiode array detection/electrospray ionization mass spectrometry.

An ultra-pressure LC (UPLC) method has been developed and validated for the quality evaluation of a traditional Chinese medicine (Radix Linderae) by chemical fingerprint analysis with chromatograms collected at two wavelengths (260 and 320 nm). Eleven characteristic peaks in the fingerprints were identified by comparing their retention times, UV spectra and ESI-MS/MS data with those of the reference substances or the data in the literatures. Both correlation coefficient of similarities in chromatograms and relative peak areas of common peaks were calculated for quality expression of the Radix Linderae samples collected from different areas in China. The results showed high variation of relative peak area and correlation coefficients among the samples collected from various habitats, which indicated that the quality consistency of Radix Linderae is still a problem worthy of serious concern.

[Identification of keystone predators in Haizhou Bay food web based on the revised SURF index]. / 基于改进的SURFæŒ‡æ•°ç”„é€‰æµ·å·žæ¹¾é±¼ç±»ç¾¤è½çš„å ³é”®æ•é£Ÿè€ .

Keystone predator species play an important role in regulating the number, richness and distribution of prey species. Based on the bottom trawl surveys in Haizhou Bay, keystone predator species in fish communities were identified by the revised SURF (supportive role to fishery ecosystems) index. Conger myriaster, Saurida elongata, Hexagrammos otakii, Chelidonichthys spinosus, and Larimichthys polyactis were the keystone predators in the fish community. They had high number of nodes degree, and were also the main predators of many species. Further, they had strong ability of clustering. The fluctuations of their density would have great impacts on ecosystem energy flow and food web structure. The method not only considered the feeding ratio between species, but also took the amount of catch and abundance of species as important factors in the identification of keystone predators. Compared with the traditional method, this method had great improvement and provided a new one for the identification of key predators. Our results showed that the strong inter-specific interactions played an important role in maintaining the structure and function of food webs. Protection of key predators would benefit the stability of biological communities and species diversity. Therefore, ecosystem-based fisheries management (EBFM) should give priority to the protection of key species. The important economic fish species, C. myriaster and L. polyactis, should be protected with high priority as they suffered from higher fishing pressure.