Molecular characterization and identification of facilitative glucose transporter 2 (GLUT2) and its expression and of the related glycometabolism enzymes in response to different starch levels in blunt snout bream (<Emphasis Type="Italic">Megalobrama amblycephala</Emphasis>)

Facilitative glucose transporters (GLUT) are transmembrane transporters involved in glucose transport across the plasma membrane. In this study, blunt snout bream GLUT2 gene was cloned, and its expression in various tissues and in liver in response to diets with different carbohydrate levels (17.1; 21.8; 26.4; 32.0; 36.3; and 41.9% of dry matter). Blunt snout bream GLUT2 was also characterized. A full-length cDNA fragment of 2577 bp was cloned, which contains a 5′-untranslated region (UTR) of 73 bp, a 3′-UTR of 992 bp, and an open reading frame of 1512 bp that encodes a polypeptide of 503 amino acids with predicted molecular mass of 55.046 kDa and theoretical isoelectric point was 7.52. The predicted GLUT2 protein has 12 transmembrane domains between amino acid residues at 7–29; 71–93; 106–123; 133–155; 168–190; 195–217; 282–301; 316–338; 345–367; 377–399; 412–434; and 438–460. Besides, the conservative structure domains located at 12–477 amino acids belong to the sugar porter family which is the major facilitator superfamily (MFS) of transporters. Blunt snout bream GLUT2 had the high degree of sequence identity to four GLUT2s from zebrafish, chicken, human, and mouse, with 91, 63, 57, and 54% identity, respectively. Quantitative real-time (qRT) PCR assays revealed that GLUT2 expression was high in the liver, intestine, and kidney; highest in the liver and was regulated by carbohydrate intake. Compared with the control group (17.1%), fed by 3 h with higher starch levels (32.0; 36.3; and 41.9%), increased plasma glucose levels and glycemic level went back to basal by 24 h after treatment. Furthermore, higher dietary starch levels significantly increase GLUT2, glucokinase (GK), and pyruvate kinase (PK) expression and concurrently decrease phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6P) mRNA levels (P?<?0.05), and these changes were also back to basal levels after 24 h of any dietary treatment. These results indicate that the blunt snout bream is able to regulate their ability to metabolize glucose by improving GLUT2, GK, and PK expression levels and decreasing PEPCK and G6P expression levels.     

Effects of stocking density,ration and temperature on growth,survival and metamorphosis of auricularia larvae of the California sea cucumber,Parastichopus californicus

The combined effects of stocking density (0.2, 0.5, 1, 2, 4 and 8 inds/ml) and dietary microalgal ration (20,000 and 40,000 cells/ml) and the sole effect of temperature (10, 12, 14, 16, 18 and 22°C) on the specific growth rate (SGR), per cent survival and per cent metamorphosis of auricularia larvae of the California sea cucumber, Parastichopus californicus, were evaluated in two separate experiments. The SGR was not significantly affected by stocking densities in the range of 0.2 to 4 inds/ml, but was significantly reduced at 8 inds/ml. The SGR of larvae fed 20,000 cells/ml was significantly reduced in comparison to those fed 40,000 cells/ml. Larvae had significantly higher per cent survival and per cent metamorphosis when reared at densities of 0.2 and 0.5 inds/ml compared with those reared at 2–8 inds/ml. Microalgal ration level did not significantly impact survival or metamorphosis. Larvae reared at 16 and 18°C had significantly higher SGRs and per cent metamorphosis than those held at all other temperatures, while per cent survival was highest at 16°C. Based on these results, we recommend rearing auricularia larvae of P. californicus at a stocking density at or below 0.5 inds/ml, a dietary ration of 40,000 cells/ml, and a temperature of 16°C.     

湖南省及自然保护区蝶类资源记述及保护利用研究

对湖南省及自然保护区蝶类8 000 余号标本的鉴定,确定湖南省及各自然保护区蝶类284 种,隶属于11 科132 属,其中凤蝶科13 属32 种、粉蝶科9 属24 种、斑蝶科4 属7 种、环蝶科3属3 种、眼蝶科14 属51 种、蛱蝶科37 属82 种、珍蝶科1 属1 种、喙蝶科1 属2 种、蚬蝶科2 属4种、灰蝶科23 属35 种、弄蝶科25 属43 种。对已鉴定的标本抽取有详细分布资料的240 种进行区系分析,得出湖南省蝶类在世界动物地理区划中,以东洋区种为主,占38.33% ,中国特有种占26.67% ,古北区种占15.42% ,古北- 东洋共有种占13.32% ,其他组合比例较低;湖南蝶类在中国地理区划中,以华中- 华南共有种、华中-华南- 西南共有种为主,分别占17.50% 和16.25% ,其次华中- 华南- 青藏共有种占12.08% ,其他组合比例较低;对湖南省240 种蝶类在湖南4 个农业区的归属进行分析,得出其在湘西农业区所占比重为25.83% ,四区共有种20.83% ,其它农业区及组合所占比重较低。并提出了蝶类资源保护与利用措施。     

ABB~(TM)消毒剂的研发

病毒病是危害畜禽健康的主要疾病，消毒是预防和消灭传染病的最主要的措施。ABB~（TM）消毒剂具有良好的杀病毒能力，弥补了其它消毒剂的致命缺点—杀病毒能力弱或不具有杀病毒能力或其它因素影响了杀病毒效果。ABB~（TM）是一种优秀的环境消毒专用消毒剂。     

底框-抗震墙结构设计中应注意的几个问题

商住多层建筑近年来在城市中很常见,即将一层做商场、车库,然后在其上建造住宅或写字楼等建筑。此种结构形式实际计算属下柔上刚,对抗震极为不利。本文叙述了底框一抗震墙在设计时应注意的几个问题。     

黑龙江的鱼类区系

作者根据多年来对黑龙江水系鱼类调查所获标本和参考文献资料，对 黑龙江鱼类区系进行了研究。黑龙江水系共有鱼类120种（包括8亚种），隶属82属24科；河口海淡水鱼类和溯河性鱼类为22种，纯属淡水鱼类计89种，尚包括移植放流鱼类6种，土著鱼类仅为92种。     

稻田养殖克氏原螯虾关键技术探讨

克氏原螯虾俗称小龙虾,是淡水经济虾类,因可食部分较多、肉质细嫩、味道鲜美、营养价值高、蛋白质含量高的优点深受人们的欢迎.其养殖业也逐步引起人们的重视,由于稻田养殖克氏原螯虾可以把种植业与养殖业有机结合起来,充分利用人工建设的生态系统,使其发挥各自的作用.正因为有这样的优点,很多地方都开展了稻田养殖克氏原螯虾的试验[1-3].     

南昌市水生观赏植物在园林规划中的应用

水生观赏植物是营造园林水体景观的重要植物材料,它们不仅具有很高的观赏价值,而且还可以净化和改善水质。在当前城市化进程加速、可利用资源不断减少、水生态环境破坏严重的情况下,探讨发挥水生植物群落所形成的景观效果和生态效应,具有深远的意义。江西省水资源丰富,水生植物种类繁多,其中就有不少种类具有很高的观赏价值。近年来,南昌市园林水景建设蓬勃发展,水生观赏植物在水景建设中被广泛应用。本文对南昌市水生观赏植物在园林应用的现状进行了实地跟踪调查,并在此基础上对水生植物造景进行了较为系统的研究,希望为丰富水生植物景观的物种多样性和景观多样性,以及为水生观赏植物的进一步推广应用提供良好的借鉴。     

Use of supplemental amino acids on the success of reducing dietary protein levels for Jian carp (Cyprinus carpio var. Jian)

A feeding trial was conducted to investigate the effects of essential amino acids (EAA) supplementation on the success of dietary protein reduction for Jian carp (Cyprinus carpio var. Jian). Five diets were formulated including a positive control (Diet 1, 378.4 g/kg protein), a negative control (Diet 5, 289.8 g/kg protein) and three test diets (Diet 2‐Diet 4, 340.4–299.0 g/kg protein supplemented with EAA). No significant decline of growth performance in fish fed decreased dietary protein with EAA supplementation, which were significantly higher than the negative control. The apparent digestibility coefficients (ADC) of protein and most EAAs were not significantly affected by the dietary treatments. Dietary treatments did not affect whole‐body composition, but influenced protein and EAAs retentions. Total ammonia nitrogen (TAN) excretion decreased with the decreasing dietary protein, and the highest plasma ammonia content was observed in fish fed Diet 5. Plasma glucose concentration increased with the decreasing dietary protein reduction, while other plasma parameters were not affected by dietary treatments. These results indicated that low‐protein diets (299.0 g/kg) supplemented with EAA can maintain protein, EAA digestibility and retention in Jian carp, and also has benefit in the reduction of TAN excretion.     

Essential amino acids supplementation to practical diets affects growth,feed utilization and glucose metabolism‐related signalling molecules of blunt snout bream (Megalobrama amblycephala)

Six diets were formulated to investigate the success of fish meal (FM) replacement by plant proteins; diet 1 reflected a commercial feed (8% FM), diet 3 contained 4% FM, and diet 5 was devoid of FM. Whereas, diet 2, diet 4, and diet 6 reflected diet 1, diet 3, diet 5, respectively, and supplemented with essential amino acid (EAA). At the end of 8‐week trial, there was no significant difference in survival rate. Significantly higher final weight, weight gain rate, and specific growth rate were recorded in the group fed diet 2 compared with the other treatments (except diet 4) (p < 0.05). Feed conversion ratio of fish fed diet 2 was significantly lower than those fed diets 1, 3, and 5 (p < 0.05). The lowest feed intake and highest protein efficiency rate were found in fish fed diet 2 (p < 0.05). There was no significant difference in whole body compositions between treatments. Plasma aspartate transaminases, alanine aminotransferase, and glucose were significantly affected by dietary treatments (p < 0.05), while plasma protein and albumin contents were not influenced by the treatments. The relative expression of target of rapamycin (TOR) and phosphatidylinositol 3‐kinase, regulatory subunit 1 (alpha) (PIK3R1) in fish fed diet 3 (4% FM) were significantly down‐regulated compared with those fed diet 6 for TOR and diets 4 and 6 for PIK3R1 (p < 0.05). Insulin receptor substrate 1 (IRS‐1) and janus kinase 3 (JAK3) expressions were fluctuated, with the higher levels in fish fed diets 4 and 6. In conclusion, the findings of this study indicate that plant protein mixture supplemented with EAA could be used to substitute FM in practical diet for Megalobrama amblycephala.