Characterization of ghrelin mRNA expression in fasting Larimichthys crocea juveniles     

Feng Liu  Xiaokang Lv  Tianqi Chu  Mengjie Wang  Wei Zhan  Bao Lou 《海洋学报(英文版)》2021,40(6):35-40

Larimichthys crocea is a marine fish species cultured in China.Short-term starvation is often applied to improve the quality of cultured L.crocea,and the expression of ghrelin in tissues of stomach,muscle,brain,intestines,liver,and kidney,involved in starvation response,under starvation conditions were studied to understand the effect of starvation on the expression of ghrelin in L.crocea juveniles.The ghrelin expression was tissue-specific,and expression was significantly higher in the stomach compared to other tissues(P0.01).Additionally,ghrelin expression in different tissues changed along with prolongation of fasting.In the stomach,ghrelin expression levels increased gradually at the beginning of the fast,and then declined after eight days of fasting.Gene expression in the brain and intestines increased at the beginning of the fast,and then decreased with longer fasting time.Interestingly,ghrelin expression declined at the beginning of the fast,then increased with longer fasting in the kidneys and muscles.These results suggest that ghrelin is involved in starvation response in L.crocea juveniles.This study provids insights into ghrelin function and an important reference for the development of reasonable feeding strategies for L.crocea juveniles.  相似文献   

Numeric modelling and risk assessment of pollutions in the Chinese Bohai Sea     

YongZhi Liu  YouLi Shen  XianQing Lv  Qiang Liu 《中国科学:地球科学(英文版)》2017,60(8):1546-1557

To simulate the dynamic process of total nitrogen (TN) in seas, numerical modelling combined with the adjoint method is implemented in this study. Because nonpoint source terms (ST) and initial values (IV) of TN are essential but difficult to determine, the adjoint method was applied to a numerical model, and the ST and IV terms of TN were inverted via routine monitoring data in the Bohai Sea. In twin experiments, the adjoint method was capable of inverting the prescribed spatio-temporally distributed ST and the spatial distributed IV. In practical experiments, the results demonstrated that the simulation precision with ST inversion was higher than that with IV inversion and was accurate with joint initial values and source term (IST) inversion. This result indicates that nonpoint source TN is essential for the simulation of TN concentration. Furthermore, the simulated results indicate that the pollution in three bays of the Bohai Sea is rather severe. The model in this study is not specific to the Bohai Sea and can be generalized to other areas, such as the Beibu Gulf. These findings may assist in the development of cost-effective controls for accidental or planned industrial pollutant releases into coastal waters.  相似文献   

基于遥感反射率的太湖优势藻识别方法     

朱雨新  李云梅  张玉  王怀警  蔡小兰  成鑫  吕恒 《湖泊科学》2023,35(1):73-87

我国淡水湖库频发水华,不同类群形成的水华特征、危害及其治理方法差异显著,因此,如何区分不同藻种的遥感反射率特征,获取湖泊优势种信息是一个亟待解决的科学问题。研究基于室内藻种培养实验,培养了富营养化湖泊中的典型蓝藻和绿藻藻种,其中,蓝藻包括铜绿微囊藻（Microcystis aeruginosa）、假鱼腥藻（Pseudanabaenasp．）和束丝藻（Aphanizomenonsp．）,绿藻包括小球藻（Chlorellasp．）以及四尾栅藻（Scenedesmus quadricauda）;基于实测的遥感反射率,经归一化处理后,分析了不同藻种的遥感反射率特征,构建了DI(difference index)指数以及ADI(algae distinguish index)指数,建立了藻种分类模型,利用验证集数据进行检验,整体识别精度达77.55%,Kappa系数为0.7178。将分类方法应用于太湖野外实测遥感反射率数据集中,结果与实测的生物量数据有较好的匹配;将模型应用于太湖OLCI(ocean and land colour instrument)影像数据,获得了2019年12月和2020...  相似文献   

邢台地区设定地震事件烈度影响   总被引：1，自引：1，他引：0  

吕国军  张合  李皓  孙丽娜 《地震地磁观测与研究》2017,38(4):37-44

通过邢台地区历史地震烈度资料分析,得到该地区烈度—频率灾害曲线及地震风险。以地震地质资料理论为基础,结合河北省城市活断层探测成果、地壳结构等资料,确定2个设定地震事件。采用复合震源模型,模拟合成强地面运动,并基于强地面运动模拟结果,分析邢台地区地震影响烈度,为今后该地区建筑物抗震设防、避难场所选址、震后救援以及地震保险风险评估提供参考依据。  相似文献   

浙江省地震观测台站综合防雷系统升级     

张明  李慧峰  吕奥博  邱晓宇 《地震地磁观测与研究》2017,38(3):175-179

以2014年浙江省地震局5个地震台站进行综合防雷系统升级改造为例,阐述浙江省数字观测台站雷击隐患,从配电系统、接地系统、通信系统和综合布线等方面出发,结合台站实际情况,对地质环境特殊的台站进行针对性防护,总结此次防雷系统改造的实际效果,分析不足之处,提出后续改造建议。  相似文献   

Assessing flood risk in Baiyangdian Lake area in a changing climate using an integrated hydrological-hydrodynamic modelling     

Y. Wang  X. Zhang  M. Mu  C. Zhang  A. Lv 《水文科学杂志》2019,64(16):2006-2014

ABSTRACT

Flood-risk is affected by both climatic and anthropogenic factors. In this study, we assess changes in flood risk induced by a combination of climate change and flood prevention sets in the Baiyangdian (BYD) Lake area of China. Extreme storm events are analysed by the bias-corrected climate data from global climate models. A hydrological model is implemented and integrated with a hydrodynamic model to assess flood risk under three scenarios. The streamflow into the BYD was validated against historical flash-flood events. The results indicate that the changing climate increased extreme precipitation, upstream total inflow and the flood risk at the core region of Xiong’an New Area (XNA), the newly announced special economic zone in the BYD area. However, flood prevention measures can effectively mitigate the climatic effect. The research highlights the severe flash-flood risk at BYD and demonstrates the urgent need for a climate-resilient plan for XNA.  相似文献   

云南地震重点监视防御区民众地震科普认知分析     

吕佳丽  张方浩  李兆隆  邓树荣  曹彦波 《震灾防御技术》2019,14(4):869-881

云南地处云贵高原,地震活动频繁,是一个多震多灾的省份。当地民众对地震灾害的认知程度和自救互救能力,对于保护生命财产安全,减轻地震灾害损失,显得尤为重要。本文选取云南地震重点监视防御区为样本区域,对民众的地震科普知识认知情况和互联网信息智慧化推送接受程度等进行了调研。根据调查结果分析评价,10个样本区域民众的地震科普知识整体认知水平不高,“优秀”等级的州市为0,“良好”等级的州市有6个,“差”的州市有4个;对互联网智慧化推送的民众接受程度存在比较明显的群体差异。  相似文献   

东海南部海域夏秋季沿岸流特征   总被引：1，自引：0，他引：1  

李鹏  史本伟  李延刚  王思荐  吕忻  汪亚平  田清 《海洋学报(英文版)》2020,39(3):1-11

Current characteristics and vertical variations during summer and autumn in the southern East China Sea were investigated by measuring current profile, tide, wind, and wave data for 90 d from July 28 to October 25, 2015. Our results are:(1) The current was mainly a(clockwise) rotating flow, displaying reciprocating flow characteristics,and vertically the current directions were the same throughout the vertical profile.(2) The horizontal current speed was strongest during August(summer) with an average speed of 51.8 cm/s. The average current speeds during spring tides were highest in August and weakest in September, with speeds of 59.9 and 42.8 cm/s,respectively.(3) Considerable differences exist in average current speeds in different layers and seasons. The highest average current speeds were found in the middle–upper layers in August and in the middle–lower layers in September and October.(4) The residual current speed was highest in August, when the speed was 12.5–47.1 cm/s,whereas the vertical average current speed was 34.3 cm/s. The depth-averaged residual current speeds in September and October were only 50% of that in August, and the residual current direction gradually rotated in a counter-clockwise direction from the lower to surface layers.(5) Typhoon waves had a significant influence on the currents, and even affected the middle and lower water layers at depths of >70.0 m. Our results showed that the currents are controlled by the dynamic interplay of the Taiwan Warm Current, incursion of the Kuroshio Current onto the continental shelf, and monsoonal changes.  相似文献   

莱芜市做好土地开发整理工作   总被引：2，自引：2，他引：0  

刘文鹏  吕清秀 《山东国土资源》2009,25(7):55-56

莱芜市地处鲁中山区,地形以山区、丘陵为主,有“六山一水三分田”之说,人均耕地只有0．054hm2（0．82亩）,是全省人均耕地最少的市之一。近年来,莱芜市从人多地少的市情出发,不断强化宣传引导,完善政策措施,加大资金投入,加强项目管理,全面推进土地开发整理工作。自2000年以来,全市市级以上累计投入专项资金3．9亿元,开发整理复垦各类土地3．93万hm2,增加耕地0．98万hm2,改造中低产田1．07万hm2,在增加有效耕地面积、提高耕地质量、保障占补平衡、改善农业生产条件和生态环境、促进农村发展、农业增效、农民增收等方面取得了显著成效。  相似文献   

临朐县土地开发整理见实效          下载免费PDF全文

周俊凤  王水清  吕廷蛟 《山东国土资源》2009,25(6):54-55

临朐县土地总面积1834km^3,山地丘陵占全县土地总面积的87％。1999年国土资源部把临朐县设立为首批全国土地开发整理示范区之一,8年来,临朐县委县政府狠抓山区土地开发整理不放松,先后建设国家级土地开发整理项目2个,省级项目8个,市级项目20个,共开发整理土地2．33万hm^2,增加耕地0．47万hm^2,项目区农业、林果业生产能力提高1．2倍,农民人均纯收入翻了一番。  相似文献